Merge pull request #85 from aramperes/dependabot/cargo/async-trait-0.1.87

build(deps): bump async-trait from 0.1.83 to 0.1.87

.cargo/config.toml

@@ -0,0 +1,4 @@
+[env]
+# Each interface needs 1 IP allocated to the WireGuard peer IP.
+# "8" = 7 tunnels per protocol.
+SMOLTCP_IFACE_MAX_ADDR_COUNT = "8"

.github/ci/macos-install-packages

@@ -1,6 +1,6 @@
 #!/bin/sh
 
-brew install asciidoctor
+# brew install asciidoctor
 
-brew install openssl@1.1
+# brew install openssl@1.1
-cp /usr/local/opt/openssl@1.1/lib/pkgconfig/*.pc /usr/local/lib/pkgconfig/
+# cp /usr/local/opt/openssl@1.1/lib/pkgconfig/*.pc /usr/local/lib/pkgconfig/

.github/dependabot.yml

@@ -0,0 +1,10 @@
+# Please see the documentation for all configuration options:
+# https://help.github.com/github/administering-a-repository/configuration-options-for-dependency-updates
+
+version: 2
+updates:
+  - package-ecosystem: "cargo"
+    directory: "/"
+    schedule:
+      interval: "weekly"
+    rebase-strategy: "disabled"

.github/workflows/build.yml

@@ -10,7 +10,7 @@ jobs:
       matrix:
         rust:
           - stable
-          - 1.55.0
+          - 1.80.0
     steps:
       - name: Checkout sources
         uses: actions/checkout@v2
@@ -26,6 +26,12 @@ jobs:
         with:
           command: check
 
+      - name: Run cargo check without default features
+        uses: actions-rs/cargo@v1
+        with:
+          command: check
+          args: --no-default-features
+
   test:
     name: Test Suite
     runs-on: ubuntu-latest
@@ -33,7 +39,7 @@ jobs:
       matrix:
         rust:
           - stable
-          - 1.55.0
+          - 1.80.0
     steps:
       - name: Checkout sources
         uses: actions/checkout@v2

.github/workflows/release.yml

@@ -61,7 +61,7 @@ jobs:
         run: echo "${{ env.VERSION }}" > artifacts/release-version
 
       - name: Upload artifacts
-        uses: actions/upload-artifact@v1
+        uses: actions/upload-artifact@v4
         with:
           name: artifacts
           path: artifacts
@@ -75,20 +75,28 @@ jobs:
       RUST_BACKTRACE: 1
     strategy:
       matrix:
-        build: [ linux-amd64, macos-intel, windows ]
+        build: [ linux-amd64, linux-aarch64, macos-aarch64, windows ]
         include:
           - build: linux-amd64
-            os: ubuntu-18.04
+            os: ubuntu-latest
             rust: stable
             target: x86_64-unknown-linux-musl
-          - build: macos-intel
+            cross: true
+          - build: linux-aarch64
+            os: ubuntu-latest
+            rust: stable
+            target: aarch64-unknown-linux-musl
+            cross: true
+          - build: macos-aarch64
             os: macos-latest
             rust: stable
-            target: x86_64-apple-darwin
+            target: aarch64-apple-darwin
+            cross: false
           - build: windows
             os: windows-2019
             rust: stable
             target: x86_64-pc-windows-msvc
+            cross: false
 
     steps:
       - name: Checkout repository
@@ -97,7 +105,7 @@ jobs:
           fetch-depth: 1
 
       - name: Install packages (Ubuntu)
-        if: matrix.os == 'ubuntu-18.04'
+        if: matrix.os == 'ubuntu-latest'
         run: |
           .github/ci/ubuntu-install-packages
       - name: Install packages (macOS)
@@ -113,7 +121,7 @@ jobs:
           target: ${{ matrix.target }}
 
       - name: Get release download URL
-        uses: actions/download-artifact@v1
+        uses: actions/download-artifact@v4
         with:
           name: artifacts
           path: artifacts
@@ -126,17 +134,24 @@ jobs:
           echo "release upload url: $release_upload_url"
 
       - name: Build onetun binary
-        run: cargo build --release
+        shell: bash
+        run: |
+          if [ "${{ matrix.cross }}" = "true" ]; then
+            cargo install cross
+            cross build --release --target ${{ matrix.target }}
+          else
+            cargo build --release --target ${{ matrix.target }}
+          fi
 
       - name: Prepare onetun binary
         shell: bash
         run: |
           mkdir -p ci/assets
           if [ "${{ matrix.build }}" = "windows" ]; then
-            cp "target/release/onetun.exe" "ci/assets/onetun.exe"
+            cp "target/${{ matrix.target }}/release/onetun.exe" "ci/assets/onetun.exe"
             echo "ASSET=onetun.exe" >> $GITHUB_ENV
           else
-            cp "target/release/onetun" "ci/assets/onetun-${{ matrix.build }}"
+            cp "target/${{ matrix.target }}/release/onetun" "ci/assets/onetun-${{ matrix.build }}"
             echo "ASSET=onetun-${{ matrix.build }}" >> $GITHUB_ENV
           fi
 

.gitignore

@@ -2,3 +2,5 @@
 /.idea
 .envrc
 *.log
+*.pcap
+.DS_Store

Cargo.toml

@@ -1,21 +1,48 @@
 [package]
 name = "onetun"
-version = "0.2.2"
+version = "0.3.10"
-edition = "2018"
+edition = "2021"
+license = "MIT"
+description = "A cross-platform, user-space WireGuard port-forwarder that requires no system network configurations."
+authors = ["Aram Peres <aram.peres@gmail.com>"]
+repository = "https://github.com/aramperes/onetun"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
-boringtun = { git = "https://github.com/cloudflare/boringtun", rev = "fbcf2689e7776a5af805c5a38feb5c8988829980", default-features = false }
+# Required dependencies (bin and lib)
-clap = { version = "2.33", default-features = false, features = ["suggestions"] }
+boringtun = { version = "0.6.0", default-features = false }
 log = "0.4"
-pretty_env_logger = "0.4"
 anyhow = "1"
-smoltcp = { version = "0.8.0", default-features = false, features = ["std", "log", "medium-ip", "proto-ipv4", "proto-ipv6", "socket-udp", "socket-tcp"] }
+tokio = { version = "1", features = [ "rt", "sync", "io-util", "net", "time", "fs", "macros" ] }
-tokio = { version = "1", features = ["full"] }
+futures = "0.3"
-futures = "0.3.17"
+rand = "0.8"
-rand = "0.8.4"
 nom = "7"
-async-trait = "0.1.51"
+async-trait = "0.1"
-dashmap = "4.0.2"
+priority-queue = "2.1"
-priority-queue = "1.2.0"
+smoltcp = { version = "0.12", default-features = false, features = [
+    "std",
+    "log",
+    "medium-ip",
+    "proto-ipv4",
+    "proto-ipv6",
+    "socket-udp",
+    "socket-tcp",
+] }
+bytes = "1"
+base64 = "0.13"
+
+# forward boringtuns tracing events to log
+tracing = { version = "0.1", default-features = false, features = ["log"] }
+
+# bin-only dependencies
+clap = { version = "4.4.11", default-features = false, features = ["suggestions", "std", "env", "help", "wrap_help"], optional = true }
+pretty_env_logger = { version = "0.5", optional = true }
+async-recursion = "1.0"
+
+[features]
+pcap = []
+default = [ "bin" ]
+bin = [ "clap", "pretty_env_logger", "pcap", "tokio/rt-multi-thread" ]
+
+[lib]

Dockerfile

@@ -1,10 +1,11 @@
-FROM rust:1.55 as cargo-build
+FROM rust:1.82.0 as cargo-build
 
 WORKDIR /usr/src/onetun
 COPY Cargo.toml Cargo.toml
 
 # Placeholder to download dependencies and cache them using layering
 RUN mkdir src/
+RUN touch src/lib.rs
 RUN echo "fn main() {println!(\"if you see this, the build broke\")}" > src/main.rs
 RUN cargo build --release
 RUN rm -f target/x86_64-unknown-linux-musl/release/deps/myapp*
@@ -14,8 +15,9 @@ COPY . .
 RUN cargo build --release
 
 FROM debian:11-slim
-RUN apt-get update
+RUN apt-get update \
-RUN apt-get install dumb-init -y
+    && apt-get install dumb-init -y \
+    && rm -rf /var/lib/apt/lists/*
 
 COPY --from=cargo-build /usr/src/onetun/target/release/onetun /usr/local/bin/onetun
 

LICENSE

@@ -1,6 +1,6 @@
 MIT License
 
-Copyright (c) 2021 Aram Peres
+Copyright (c) 2025 Aram Peres
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal

README.md

@@ -2,20 +2,48 @@
 
 # onetun
 
-A cross-platform, user-space WireGuard port-forwarder that requires no system network configurations.
+A cross-platform, user-space WireGuard port-forwarder that requires **no root-access or system network configurations**.
 
+[![crates.io](https://img.shields.io/crates/v/onetun.svg)](https://crates.io/crates/onetun)
+[![MIT licensed](https://img.shields.io/crates/l/onetun.svg)](./LICENSE)
 [![Build status](https://github.com/aramperes/onetun/actions/workflows/build.yml/badge.svg)](https://github.com/aramperes/onetun/actions)
 [![Latest Release](https://img.shields.io/github/v/tag/aramperes/onetun?label=release)](https://github.com/aramperes/onetun/releases/latest)
 
 ## Use-case
 
-- You have an existing WireGuard endpoint (router), accessible using its UDP endpoint (typically port 51820); and
+Access TCP or UDP services running on your WireGuard network, from devices that don't have WireGuard installed.
-- You have a peer on the WireGuard network, running a TCP or UDP service on a port accessible to the WireGuard network; and
-- You want to access this TCP or UDP service from a second computer, on which you can't install WireGuard because you
-  can't (no root access) or don't want to (polluting OS configs).
 
-For example, this can be useful to forward a port from a Kubernetes cluster to a server behind WireGuard,
+For example,
-without needing to install WireGuard in a Pod.
+
+- Personal or shared computers where you can't install WireGuard (root)
+- IoT and mobile devices
+- Root-less containers
+
+## Download
+
+onetun is available to install from [crates.io](https://crates.io/crates/onetun) with Rust ≥1.80.0:
+
+```shell
+cargo install onetun
+```
+
+You can also download the binary for Windows, macOS (Apple Silicon), and Linux (amd64, arm64) from
+the [Releases](https://github.com/aramperes/onetun/releases) page.
+
+You can also run onetun using [Docker](https://hub.docker.com/r/aramperes/onetun):
+
+```shell
+docker run --rm --name onetun --user 1000 -p 8080:8080 aramperes/onetun \
+    0.0.0.0:8080:192.168.4.2:8080 [...options...]
+```
+
+You can also build onetun locally, using Rust ≥1.80.0:
+
+```shell
+git clone https://github.com/aramperes/onetun && cd onetun
+cargo build --release
+./target/release/onetun
+```
 
 ## Usage
 
@@ -26,14 +54,14 @@ access, or install any WireGuard tool on your local system for it to work.
 The only prerequisite is to register a peer IP and public key on the remote WireGuard endpoint; those are necessary for
 the WireGuard endpoint to trust the onetun peer and for packets to be routed.
 
-```
+```shell
-./onetun [src_host:]<src_port>:<dst_host>:<dst_port>[:TCP,UDP,...] [...]  \
+onetun [src_host:]<src_port>:<dst_host>:<dst_port>[:TCP,UDP,...] [...]    \
     --endpoint-addr <public WireGuard endpoint address>                   \
     --endpoint-public-key <the public key of the peer on the endpoint>    \
     --private-key <private key assigned to onetun>                        \
     --source-peer-ip <IP assigned to onetun>                              \
     --keep-alive <optional persistent keep-alive in seconds>              \
-    --log <optional log level, defaults to "info"
+    --log <optional log level, defaults to "info">
 ```
 
 > Note: you can use environment variables for all of these flags. Use `onetun --help` for details.
@@ -42,7 +70,7 @@ the WireGuard endpoint to trust the onetun peer and for packets to be routed.
 
 Suppose your WireGuard endpoint has the following configuration, and is accessible from `140.30.3.182:51820`:
 
-```
+```shell
 # /etc/wireguard/wg0.conf
 
 [Interface]
@@ -65,7 +93,7 @@ We want to access a web server on the friendly peer (`192.168.4.2`) on port `808
 local port, say `127.0.0.1:8080`, that will tunnel through WireGuard to reach the peer web server:
 
 ```shell
-./onetun 127.0.0.1:8080:192.168.4.2:8080                                  \
+onetun 127.0.0.1:8080:192.168.4.2:8080                                    \
     --endpoint-addr 140.30.3.182:51820                                    \
     --endpoint-public-key 'PUB_****************************************'  \
     --private-key 'PRIV_BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB'          \
@@ -75,14 +103,14 @@ local port, say `127.0.0.1:8080`, that will tunnel through WireGuard to reach th
 
 You'll then see this log:
 
-```
+```shell
 INFO  onetun > Tunneling TCP [127.0.0.1:8080]->[192.168.4.2:8080] (via [140.30.3.182:51820] as peer 192.168.4.3)
 ```
 
 Which means you can now access the port locally!
 
-```
+```shell
-$ curl 127.0.0.1:8080
+curl 127.0.0.1:8080
 Hello world!
 ```
 
@@ -90,24 +118,32 @@ Hello world!
 
 **onetun** supports running multiple tunnels in parallel. For example:
 
-```
+```shell
-$ ./onetun 127.0.0.1:8080:192.168.4.2:8080 127.0.0.1:8081:192.168.4.4:8081
+onetun 127.0.0.1:8080:192.168.4.2:8080 127.0.0.1:8081:192.168.4.4:8081
 INFO  onetun::tunnel > Tunneling TCP [127.0.0.1:8080]->[192.168.4.2:8080] (via [140.30.3.182:51820] as peer 192.168.4.3)
 INFO  onetun::tunnel > Tunneling TCP [127.0.0.1:8081]->[192.168.4.4:8081] (via [140.30.3.182:51820] as peer 192.168.4.3)
 ```
 
 ... would open TCP ports 8080 and 8081 locally, which forward to their respective ports on the different peers.
 
+#### Maximum number of tunnels
+
+`smoltcp` imposes a compile-time limit on the number of IP addresses assigned to an interface. **onetun** increases
+the default value to support most use-cases. In effect, the default limit on the number of **onetun** peers
+is **7 per protocol** (TCP and UDP).
+
+Should you need more unique IP addresses to forward ports to, you can increase the limit in `.cargo/config.toml` and recompile **onetun**.
+
 ### UDP Support
 
 **onetun** supports UDP forwarding. You can add `:UDP` at the end of the port-forward configuration, or `UDP,TCP` to support
 both protocols on the same port (note that this opens 2 separate tunnels, just on the same port)
 
-```
+```shell
-$ ./onetun 127.0.0.1:8080:192.168.4.2:8080:UDP
+onetun 127.0.0.1:8080:192.168.4.2:8080:UDP
 INFO  onetun::tunnel > Tunneling UDP [127.0.0.1:8080]->[192.168.4.2:8080] (via [140.30.3.182:51820] as peer 192.168.4.3)
 
-$ ./onetun 127.0.0.1:8080:192.168.4.2:8080:UDP,TCP
+onetun 127.0.0.1:8080:192.168.4.2:8080:UDP,TCP
 INFO  onetun::tunnel > Tunneling UDP [127.0.0.1:8080]->[192.168.4.2:8080] (via [140.30.3.182:51820] as peer 192.168.4.3)
 INFO  onetun::tunnel > Tunneling TCP [127.0.0.1:8080]->[192.168.4.2:8080] (via [140.30.3.182:51820] as peer 192.168.4.3)
 ```
@@ -119,61 +155,77 @@ it in any production capacity.
 
 **onetun** supports both IPv4 and IPv6. In fact, you can use onetun to forward some IP version to another, e.g. 6-to-4:
 
-```
+```shell
-$ ./onetun [::1]:8080:192.168.4.2:8080
+onetun [::1]:8080:192.168.4.2:8080
 INFO  onetun::tunnel > Tunneling TCP [[::1]:8080]->[192.168.4.2:8080] (via [140.30.3.182:51820] as peer 192.168.4.3)
 ```
 
 Note that each tunnel can only support one "source" IP version and one "destination" IP version. If you want to support
 both IPv4 and IPv6 on the same port, you should create a second port-forward:
 
-```
+```shell
-$ ./onetun [::1]:8080:192.168.4.2:8080 127.0.0.1:8080:192.168.4.2:8080
+onetun [::1]:8080:192.168.4.2:8080 127.0.0.1:8080:192.168.4.2:8080
 INFO  onetun::tunnel > Tunneling TCP [[::1]:8080]->[192.168.4.2:8080] (via [140.30.3.182:51820] as peer 192.168.4.3)
 INFO  onetun::tunnel > Tunneling TCP [127.0.0.1:8080]->[192.168.4.2:8080] (via [140.30.3.182:51820] as peer 192.168.4.3)
 ```
 
-## Download
+### Packet Capture
 
-Normally I would publish `onetun` to crates.io. However, it depends on some features
+For debugging purposes, you can enable the capture of IP packets sent between onetun and the WireGuard peer.
-in [smoltcp](https://github.com/smoltcp-rs/smoltcp) and
+The output is a libpcap capture file that can be viewed with Wireshark.
-[boringtun](https://github.com/cloudflare/boringtun) that haven't been published yet, so I'm forced to use their Git
-repos as dependencies for now.
-
-In the meantime, you can download the binary for Windows, macOS (Intel), and Linux (amd64) from
-the [Releases](https://github.com/aramperes/onetun/releases) page.
-
-You can also run onetun using [Docker](https://hub.docker.com/r/aramperes/onetun):
 
 ```shell
-docker run --rm --name onetun --user 1000 -p 8080:8080 aramperes/onetun \
+onetun --pcap wg.pcap 127.0.0.1:8080:192.168.4.2:8080
-       0.0.0.0:8080:192.168.4.2:8080 [...options...]
+INFO  onetun::pcap > Capturing WireGuard IP packets to wg.pcap
+INFO  onetun::tunnel > Tunneling TCP [127.0.0.1:8080]->[192.168.4.2:8080] (via [140.30.3.182:51820] as peer 192.168.4.3)
 ```
 
-You can also build onetun locally, using Rust:
+To capture packets sent to and from the onetun local port, you must use an external tool like `tcpdump` with root access:
 
 ```shell
-$ git clone https://github.com/aramperes/onetun && cd onetun
+sudo tcpdump -i lo -w local.pcap 'dst 127.0.0.1 && port 8080'
-$ cargo build --release
+```
-$ ./target/release/onetun
+
+### WireGuard Options
+
+By default, onetun will create the UDP socket to communicate with the WireGuard endpoint on all interfaces and on a dynamic port,
+i.e. `0.0.0.0:0` for IPv4 endpoints, or `[::]:0` for IPv6.
+You can bind to a static address instead using `--endpoint-bind-addr`:
+
+```shell
+onetun --endpoint-bind-addr 0.0.0.0:51820 --endpoint-addr 140.30.3.182:51820 [...]
+```
+
+The security of the WireGuard connection can be further enhanced with a **pre-shared key** (PSK). You can generate such a key with the `wg genpsk` command, and provide it using `--preshared-key`.
+The peer must also have this key configured using the `PresharedKey` option.
+
+```shell
+onetun --preshared-key 'XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX' [...]
 ```
 
 ## Architecture
 
+**In short:** onetun uses [smoltcp's](https://github.com/smoltcp-rs/smoltcp) TCP/IP and UDP stack to generate IP packets
+using its state machine ("virtual interface"). The generated IP packets are
+encrypted by [boringtun](https://github.com/cloudflare/boringtun) and sent to the WireGuard endpoint. Encrypted IP packets received
+from the WireGuard endpoint are decrypted using boringtun and sent through the smoltcp virtual interface state machine.
+onetun creates "virtual sockets" in the virtual interface to forward data sent from inbound connections,
+as well as to receive data from the virtual interface to forward back to the local client.
+
+---
+
 onetun uses [tokio](https://github.com/tokio-rs/tokio), the async runtime, to listen for new TCP connections on the
 given port.
 
-When a client connects to the local TCP port, it uses [smoltcp](https://github.com/smoltcp-rs/smoltcp) to
+When a client connects to the onetun's TCP port, a "virtual client" is
-create a "virtual interface", with a "virtual client" and a "virtual server" for the connection. These "virtual"
+created in a [smoltcp](https://github.com/smoltcp-rs/smoltcp) "virtual" TCP/IP interface, which runs fully inside the onetun
-components are the crux of how onetun works. They essentially replace the host's TCP/IP stack with smoltcp's, which
+process. An ephemeral "virtual port" is assigned to the "virtual client", which maps back to the local client.
-fully runs inside onetun. An ephemeral "virtual port" is also assigned to the connection, in order to route packets
-back to the right connection.
 
-When the real client opens the connection, the virtual client socket opens a TCP connection to the virtual server.
+When the real client opens the connection, the virtual client socket opens a TCP connection to the virtual server
-The virtual interface (implemented by smoltcp) in turn crafts the `SYN` segment and wraps it in an IP packet.
+(a dummy socket bound to the remote host/port). The virtual interface in turn crafts the `SYN` segment and wraps it in an IP packet.
 Because of how the virtual client and server are configured, the IP packet is crafted with a source address
 being the configured `source-peer-ip` (`192.168.4.3` in the example above),
-and the destination address is the remote peer's (`192.168.4.2`).
+and the destination address matches the port-forward's configured destination (`192.168.4.2`).
 
 By doing this, we let smoltcp handle the crafting of the IP packets, and the handling of the client's TCP states.
 Instead of actually sending those packets to the virtual server,
@@ -184,8 +236,8 @@ Once the WireGuard endpoint receives an encrypted IP packet, it decrypts it usin
 It reads the destination address, re-encrypts the IP packet using the matching peer's public key, and sends it off to
 the peer's UDP endpoint.
 
-The remote peer receives the encrypted IP and decrypts it. It can then read the inner payload (the TCP segment),
+The peer receives the encrypted IP and decrypts it. It can then read the inner payload (the TCP segment),
-forward it to the server's port, which handles the TCP segment. The server responds with `SYN-ACK`, which goes back through
+forward it to the server's port, which handles the TCP segment. The TCP server responds with `SYN-ACK`, which goes back through
 the peer's local WireGuard interface, gets encrypted, forwarded to the WireGuard endpoint, and then finally back to onetun's UDP port.
 
 When onetun receives an encrypted packet from the WireGuard endpoint, it decrypts it using boringtun.
@@ -215,6 +267,56 @@ if the least recently used port hasn't been used for a certain amount of time. I
 
 All in all, I would not recommend using UDP forwarding for public services, since it's most likely prone to simple DoS or DDoS.
 
+## HTTP/SOCKS Proxy
+
+**onetun** is a Transport-layer proxy (also known as port forwarding); it is not in scope to provide
+a HTTP/SOCKS proxy server. However, you can easily chain **onetun** with a proxy server on a remote
+that is locked down to your WireGuard network.
+
+For example, you could run [dante-server](https://www.inet.no/dante/) on a peer (ex. `192.168.4.2`) with the following configuration:
+
+```
+# /etc/danted.conf
+
+logoutput: syslog
+user.privileged: root
+user.unprivileged: nobody
+
+internal: 192.168.4.2 port=1080
+external: eth0
+
+socksmethod: none
+clientmethod: none
+
+# Locks down proxy use to WireGuard peers (192.168.4.x)
+client pass {
+    from: 192.168.4.0/24 to: 0.0.0.0/0
+}
+socks pass {
+    from: 192.168.4.0/24 to: 0.0.0.0/0
+}
+```
+
+Then use **onetun** to expose the SOCKS5 proxy locally:
+
+```shell
+onetun 127.0.0.1:1080:192.168.4.2:1080
+INFO  onetun::tunnel > Tunneling TCP [127.0.0.1:1080]->[192.168.4.2:1080] (via [140.30.3.182:51820] as peer 192.168.4.3)
+```
+
+Test with `curl` (or configure your browser):
+
+```shell
+curl -x socks5://127.0.0.1:1080 https://ifconfig.me
+```
+
+## Contributing and Maintenance
+
+I will gladly accept contributions to onetun, and set aside time to review all pull-requests.
+Please consider opening a GitHub issue if you are unsure if your contribution is within the scope of the project.
+
+**Disclaimer**: I do not have enough personal time to actively maintain onetun besides open-source contributions.
+
 ## License
 
-MIT. See `LICENSE` for details.
+MIT License. See `LICENSE` for details. Copyright &copy; 2025 Aram Peres.

src/config.rs

@@ -5,34 +5,43 @@ use std::fs::read_to_string;
 use std::net::{IpAddr, SocketAddr, ToSocketAddrs};
 use std::sync::Arc;
 
-use anyhow::Context;
+use anyhow::{bail, Context};
-use boringtun::crypto::{X25519PublicKey, X25519SecretKey};
+pub use boringtun::x25519::{PublicKey, StaticSecret};
-use clap::{App, Arg};
 
-#[derive(Clone, Debug)]
+const DEFAULT_PORT_FORWARD_SOURCE: &str = "127.0.0.1";
+
+#[derive(Clone)]
 pub struct Config {
-    pub(crate) port_forwards: Vec<PortForwardConfig>,
+    pub port_forwards: Vec<PortForwardConfig>,
-    pub(crate) private_key: Arc<X25519SecretKey>,
+    #[allow(dead_code)]
-    pub(crate) endpoint_public_key: Arc<X25519PublicKey>,
+    pub remote_port_forwards: Vec<PortForwardConfig>,
-    pub(crate) endpoint_addr: SocketAddr,
+    pub private_key: Arc<StaticSecret>,
-    pub(crate) source_peer_ip: IpAddr,
+    pub endpoint_public_key: Arc<PublicKey>,
-    pub(crate) keepalive_seconds: Option<u16>,
+    pub preshared_key: Option<[u8; 32]>,
-    pub(crate) log: String,
+    pub endpoint_addr: SocketAddr,
-    pub(crate) warnings: Vec<String>,
+    pub endpoint_bind_addr: SocketAddr,
+    pub source_peer_ip: IpAddr,
+    pub keepalive_seconds: Option<u16>,
+    pub max_transmission_unit: usize,
+    pub log: String,
+    pub warnings: Vec<String>,
+    pub pcap_file: Option<String>,
 }
 
 impl Config {
+    #[cfg(feature = "bin")]
     pub fn from_args() -> anyhow::Result<Self> {
+        use clap::{Arg, Command};
+
         let mut warnings = vec![];
 
-        let matches = App::new("onetun")
+        let matches = Command::new("onetun")
             .author("Aram Peres <aram.peres@gmail.com>")
             .version(env!("CARGO_PKG_VERSION"))
             .args(&[
-                Arg::with_name("PORT_FORWARD")
+                Arg::new("PORT_FORWARD")
                     .required(false)
-                    .multiple(true)
+                    .num_args(1..)
-                    .takes_value(true)
                     .help("Port forward configurations. The format of each argument is [src_host:]<src_port>:<dst_host>:<dst_port>[:TCP,UDP,...], \
                     where [src_host] is the local IP to listen on, <src_port> is the local port to listen on, <dst_host> is the remote peer IP to forward to, and <dst_port> is the remote port to forward to. \
                     Environment variables of the form 'ONETUN_PORT_FORWARD_[#]' are also accepted, where [#] starts at 1.\n\
@@ -46,54 +55,94 @@ impl Config {
                     \tlocalhost:8080:192.168.4.1:8081:TCP\n\
                     \tlocalhost:8080:peer.intranet:8081:TCP\
                     "),
-                Arg::with_name("private-key")
+                Arg::new("private-key")
-                    .required_unless("private-key-file")
+                    .conflicts_with("private-key-file")
-                    .takes_value(true)
+                    .num_args(1)
                     .long("private-key")
                     .env("ONETUN_PRIVATE_KEY")
                     .help("The private key of this peer. The corresponding public key should be registered in the WireGuard endpoint. \
                     You can also use '--private-key-file' to specify a file containing the key instead."),
-                Arg::with_name("private-key-file")
+                Arg::new("private-key-file")
-                    .takes_value(true)
+                    .num_args(1)
                     .long("private-key-file")
                     .env("ONETUN_PRIVATE_KEY_FILE")
                     .help("The path to a file containing the private key of this peer. The corresponding public key should be registered in the WireGuard endpoint."),
-                Arg::with_name("endpoint-public-key")
+                Arg::new("endpoint-public-key")
                     .required(true)
-                    .takes_value(true)
+                    .num_args(1)
                     .long("endpoint-public-key")
                     .env("ONETUN_ENDPOINT_PUBLIC_KEY")
                     .help("The public key of the WireGuard endpoint (remote)."),
-                Arg::with_name("endpoint-addr")
+                Arg::new("preshared-key")
+                    .required(false)
+                    .num_args(1)
+                    .long("preshared-key")
+                    .env("ONETUN_PRESHARED_KEY")
+                    .help("The pre-shared key (PSK) as configured with the peer."),
+                Arg::new("endpoint-addr")
                     .required(true)
-                    .takes_value(true)
+                    .num_args(1)
                     .long("endpoint-addr")
                     .env("ONETUN_ENDPOINT_ADDR")
                     .help("The address (IP + port) of the WireGuard endpoint (remote). Example: 1.2.3.4:51820"),
-                Arg::with_name("source-peer-ip")
+                Arg::new("endpoint-bind-addr")
+                    .required(false)
+                    .num_args(1)
+                    .long("endpoint-bind-addr")
+                    .env("ONETUN_ENDPOINT_BIND_ADDR")
+                    .help("The address (IP + port) used to bind the local UDP socket for the WireGuard tunnel. Example: 1.2.3.4:30000. Defaults to 0.0.0.0:0 for IPv4 endpoints, or [::]:0 for IPv6 endpoints."),
+                Arg::new("source-peer-ip")
                     .required(true)
-                    .takes_value(true)
+                    .num_args(1)
                     .long("source-peer-ip")
                     .env("ONETUN_SOURCE_PEER_IP")
                     .help("The source IP to identify this peer as (local). Example: 192.168.4.3"),
-                Arg::with_name("keep-alive")
+                Arg::new("keep-alive")
                     .required(false)
-                    .takes_value(true)
+                    .num_args(1)
                     .long("keep-alive")
                     .env("ONETUN_KEEP_ALIVE")
                     .help("Configures a persistent keep-alive for the WireGuard tunnel, in seconds."),
-                Arg::with_name("log")
+                Arg::new("max-transmission-unit")
                     .required(false)
-                    .takes_value(true)
+                    .num_args(1)
+                    .long("max-transmission-unit")
+                    .env("ONETUN_MTU")
+                    .default_value("1420")
+                    .help("Configures the max-transmission-unit (MTU) of the WireGuard tunnel."),
+                Arg::new("log")
+                    .required(false)
+                    .num_args(1)
                     .long("log")
                     .env("ONETUN_LOG")
                     .default_value("info")
-                    .help("Configures the log level and format.")
+                    .help("Configures the log level and format."),
+                Arg::new("pcap")
+                    .required(false)
+                    .num_args(1)
+                    .long("pcap")
+                    .env("ONETUN_PCAP")
+                    .help("Decrypts and captures IP packets on the WireGuard tunnel to a given output file."),
+                Arg::new("remote")
+                    .required(false)
+                    .num_args(1..)
+                    .long("remote")
+                    .short('r')
+                    .help("Remote port forward configurations. The format of each argument is <src_port>:<dst_host>:<dst_port>[:TCP,UDP,...], \
+                    where <src_port> is the port the other peers will reach the server with, <dst_host> is the IP to forward to, and <dst_port> is the port to forward to. \
+                    The <src_port> will be bound on onetun's peer IP, as specified by --source-peer-ip. If you pass a different value for <src_host> here, it will be rejected.\n\
+                    Note: <dst_host>:<dst_port> must be reachable by onetun. If referring to another WireGuard peer, use --bridge instead (not supported yet).\n\
+                    Environment variables of the form 'ONETUN_REMOTE_PORT_FORWARD_[#]' are also accepted, where [#] starts at 1.\n\
+                    Examples:\n\
+                    \t--remote 8080:localhost:8081:TCP,UDP\n\
+                    \t--remote 8080:[::1]:8081:TCP\n\
+                    \t--remote 8080:google.com:80\
+                    "),
             ]).get_matches();
 
         // Combine `PORT_FORWARD` arg and `ONETUN_PORT_FORWARD_#` envs
         let mut port_forward_strings = HashSet::new();
-        if let Some(values) = matches.values_of("PORT_FORWARD") {
+        if let Some(values) = matches.get_many::<String>("PORT_FORWARD") {
             for value in values {
                 port_forward_strings.insert(value.to_owned());
             }
@@ -105,26 +154,68 @@ impl Config {
                 break;
             }
         }
-        if port_forward_strings.is_empty() {
-            return Err(anyhow::anyhow!("No port forward configurations given."));
-        }
 
         // Parse `PORT_FORWARD` strings into `PortForwardConfig`
         let port_forwards: anyhow::Result<Vec<Vec<PortForwardConfig>>> = port_forward_strings
             .into_iter()
-            .map(|s| PortForwardConfig::from_notation(&s))
+            .map(|s| PortForwardConfig::from_notation(&s, DEFAULT_PORT_FORWARD_SOURCE))
             .collect();
         let port_forwards: Vec<PortForwardConfig> = port_forwards
-            .with_context(|| "Failed to parse port forward config")?
+            .context("Failed to parse port forward config")?
             .into_iter()
             .flatten()
             .collect();
 
+        // Read source-peer-ip
+        let source_peer_ip = parse_ip(matches.get_one::<String>("source-peer-ip"))
+            .context("Invalid source peer IP")?;
+
+        // Combined `remote` arg and `ONETUN_REMOTE_PORT_FORWARD_#` envs
+        let mut port_forward_strings = HashSet::new();
+        if let Some(values) = matches.get_many::<String>("remote") {
+            for value in values {
+                port_forward_strings.insert(value.to_owned());
+            }
+        }
+        for n in 1.. {
+            if let Ok(env) = std::env::var(format!("ONETUN_REMOTE_PORT_FORWARD_{}", n)) {
+                port_forward_strings.insert(env);
+            } else {
+                break;
+            }
+        }
+        // Parse `PORT_FORWARD` strings into `PortForwardConfig`
+        let remote_port_forwards: anyhow::Result<Vec<Vec<PortForwardConfig>>> =
+            port_forward_strings
+                .into_iter()
+                .map(|s| {
+                    PortForwardConfig::from_notation(
+                        &s,
+                        matches.get_one::<String>("source-peer-ip").unwrap(),
+                    )
+                })
+                .collect();
+        let mut remote_port_forwards: Vec<PortForwardConfig> = remote_port_forwards
+            .context("Failed to parse remote port forward config")?
+            .into_iter()
+            .flatten()
+            .collect();
+        for port_forward in remote_port_forwards.iter_mut() {
+            if port_forward.source.ip() != source_peer_ip {
+                bail!("Remote port forward config <src_host> must match --source-peer-ip ({}), or be omitted.", source_peer_ip);
+            }
+            port_forward.source = SocketAddr::from((source_peer_ip, port_forward.source.port()));
+            port_forward.remote = true;
+        }
+
+        if port_forwards.is_empty() && remote_port_forwards.is_empty() {
+            bail!("No port forward configurations given.");
+        }
+
         // Read private key from file or CLI argument
         let (group_readable, world_readable) = matches
-            .value_of("private-key-file")
+            .get_one::<String>("private-key-file")
-            .map(is_file_insecurely_readable)
+            .and_then(is_file_insecurely_readable)
-            .flatten()
             .unwrap_or_default();
         if group_readable {
             warnings.push("Private key file is group-readable. This is insecure.".into());
@@ -133,69 +224,116 @@ impl Config {
             warnings.push("Private key file is world-readable. This is insecure.".into());
         }
 
-        let private_key = if let Some(private_key_file) = matches.value_of("private-key-file") {
+        let private_key = if let Some(private_key_file) =
+            matches.get_one::<String>("private-key-file")
+        {
             read_to_string(private_key_file)
                 .map(|s| s.trim().to_string())
-                .with_context(|| "Failed to read private key file")
+                .context("Failed to read private key file")
         } else {
             if std::env::var("ONETUN_PRIVATE_KEY").is_err() {
                 warnings.push("Private key was passed using CLI. This is insecure. \
                 Use \"--private-key-file <file containing private key>\", or the \"ONETUN_PRIVATE_KEY\" env variable instead.".into());
             }
             matches
-                .value_of("private-key")
+                .get_one::<String>("private-key")
-                .map(String::from)
+                .cloned()
-                .with_context(|| "Missing private key")
+                .context("Missing private key")
         }?;
 
+        let endpoint_addr = parse_addr(matches.get_one::<String>("endpoint-addr"))
+            .context("Invalid endpoint address")?;
+
+        let endpoint_bind_addr = if let Some(addr) = matches.get_one::<String>("endpoint-bind-addr")
+        {
+            let addr = parse_addr(Some(addr)).context("Invalid bind address")?;
+            // Make sure the bind address and endpoint address are the same IP version
+            if addr.ip().is_ipv4() != endpoint_addr.ip().is_ipv4() {
+                bail!("Endpoint and bind addresses must be the same IP version");
+            }
+            addr
+        } else {
+            // Return the IP version of the endpoint address
+            match endpoint_addr {
+                SocketAddr::V4(_) => parse_addr(Some("0.0.0.0:0"))?,
+                SocketAddr::V6(_) => parse_addr(Some("[::]:0"))?,
+            }
+        };
+
         Ok(Self {
             port_forwards,
-            private_key: Arc::new(
+            remote_port_forwards,
-                parse_private_key(&private_key).with_context(|| "Invalid private key")?,
+            private_key: Arc::new(parse_private_key(&private_key).context("Invalid private key")?),
-            ),
             endpoint_public_key: Arc::new(
-                parse_public_key(matches.value_of("endpoint-public-key"))
+                parse_public_key(matches.get_one::<String>("endpoint-public-key"))
-                    .with_context(|| "Invalid endpoint public key")?,
+                    .context("Invalid endpoint public key")?,
             ),
-            endpoint_addr: parse_addr(matches.value_of("endpoint-addr"))
+            preshared_key: parse_preshared_key(matches.get_one::<String>("preshared-key"))?,
-                .with_context(|| "Invalid endpoint address")?,
+            endpoint_addr,
-            source_peer_ip: parse_ip(matches.value_of("source-peer-ip"))
+            endpoint_bind_addr,
-                .with_context(|| "Invalid source peer IP")?,
+            source_peer_ip,
-            keepalive_seconds: parse_keep_alive(matches.value_of("keep-alive"))
+            keepalive_seconds: parse_keep_alive(matches.get_one::<String>("keep-alive"))
-                .with_context(|| "Invalid keep-alive value")?,
+                .context("Invalid keep-alive value")?,
-            log: matches.value_of("log").unwrap_or_default().into(),
+            max_transmission_unit: parse_mtu(matches.get_one::<String>("max-transmission-unit"))
+                .context("Invalid max-transmission-unit value")?,
+            log: matches
+                .get_one::<String>("log")
+                .cloned()
+                .unwrap_or_default(),
+            pcap_file: matches.get_one::<String>("pcap").cloned(),
             warnings,
         })
     }
 }
 
-fn parse_addr(s: Option<&str>) -> anyhow::Result<SocketAddr> {
+fn parse_addr<T: AsRef<str>>(s: Option<T>) -> anyhow::Result<SocketAddr> {
-    s.with_context(|| "Missing address")?
+    s.context("Missing address")?
+        .as_ref()
         .to_socket_addrs()
-        .with_context(|| "Invalid address")?
+        .context("Invalid address")?
         .next()
-        .with_context(|| "Could not lookup address")
+        .context("Could not lookup address")
 }
 
-fn parse_ip(s: Option<&str>) -> anyhow::Result<IpAddr> {
+fn parse_ip(s: Option<&String>) -> anyhow::Result<IpAddr> {
-    s.with_context(|| "Missing IP")?
+    s.context("Missing IP address")?
         .parse::<IpAddr>()
-        .with_context(|| "Invalid IP address")
+        .context("Invalid IP address")
 }
 
-fn parse_private_key(s: &str) -> anyhow::Result<X25519SecretKey> {
+fn parse_private_key(s: &str) -> anyhow::Result<StaticSecret> {
-    s.parse::<X25519SecretKey>()
+    let decoded = base64::decode(s).context("Failed to decode private key")?;
-        .map_err(|e| anyhow::anyhow!("{}", e))
+    if let Ok::<[u8; 32], _>(bytes) = decoded.try_into() {
+        Ok(StaticSecret::from(bytes))
+    } else {
+        bail!("Invalid private key")
+    }
 }
 
-fn parse_public_key(s: Option<&str>) -> anyhow::Result<X25519PublicKey> {
+fn parse_public_key(s: Option<&String>) -> anyhow::Result<PublicKey> {
-    s.with_context(|| "Missing public key")?
+    let encoded = s.context("Missing public key")?;
-        .parse::<X25519PublicKey>()
+    let decoded = base64::decode(encoded).context("Failed to decode public key")?;
-        .map_err(|e| anyhow::anyhow!("{}", e))
+    if let Ok::<[u8; 32], _>(bytes) = decoded.try_into() {
-        .with_context(|| "Invalid public key")
+        Ok(PublicKey::from(bytes))
+    } else {
+        bail!("Invalid public key")
+    }
 }
 
-fn parse_keep_alive(s: Option<&str>) -> anyhow::Result<Option<u16>> {
+fn parse_preshared_key(s: Option<&String>) -> anyhow::Result<Option<[u8; 32]>> {
+    if let Some(s) = s {
+        let decoded = base64::decode(s).context("Failed to decode preshared key")?;
+        if let Ok::<[u8; 32], _>(bytes) = decoded.try_into() {
+            Ok(Some(bytes))
+        } else {
+            bail!("Invalid preshared key")
+        }
+    } else {
+        Ok(None)
+    }
+}
+
+fn parse_keep_alive(s: Option<&String>) -> anyhow::Result<Option<u16>> {
     if let Some(s) = s {
         let parsed: u16 = s.parse().with_context(|| {
             format!(
@@ -209,17 +347,21 @@ fn parse_keep_alive(s: Option<&str>) -> anyhow::Result<Option<u16>> {
     }
 }
 
+fn parse_mtu(s: Option<&String>) -> anyhow::Result<usize> {
+    s.context("Missing MTU")?.parse().context("Invalid MTU")
+}
+
 #[cfg(unix)]
-fn is_file_insecurely_readable(path: &str) -> Option<(bool, bool)> {
+fn is_file_insecurely_readable(path: &String) -> Option<(bool, bool)> {
     use std::fs::File;
     use std::os::unix::fs::MetadataExt;
 
-    let mode = File::open(&path).ok()?.metadata().ok()?.mode();
+    let mode = File::open(path).ok()?.metadata().ok()?.mode();
     Some((mode & 0o40 > 0, mode & 0o4 > 0))
 }
 
 #[cfg(not(unix))]
-fn is_file_insecurely_readable(path: &str) -> Option<(bool, bool)> {
+fn is_file_insecurely_readable(_path: &String) -> Option<(bool, bool)> {
     // No good way to determine permissions on non-Unix target
     None
 }
@@ -232,6 +374,8 @@ pub struct PortForwardConfig {
     pub destination: SocketAddr,
     /// The transport protocol to use for the port (Layer 4).
     pub protocol: PortProtocol,
+    /// Whether this is a remote port forward.
+    pub remote: bool,
 }
 
 impl PortForwardConfig {
@@ -254,7 +398,7 @@ impl PortForwardConfig {
     ///  - IPv6 addresses must be prefixed with `[` and suffixed with `]`. Example: `[::1]`.
     ///  - Any `u16` is accepted as `src_port` and `dst_port`
     ///  - Specifying protocols (`PROTO1,PROTO2,...`) is optional and defaults to `TCP`. Values must be separated by commas.
-    pub fn from_notation(s: &str) -> anyhow::Result<Vec<PortForwardConfig>> {
+    pub fn from_notation(s: &str, default_source: &str) -> anyhow::Result<Vec<PortForwardConfig>> {
         mod parsers {
             use nom::branch::alt;
             use nom::bytes::complete::is_not;
@@ -332,28 +476,22 @@ impl PortForwardConfig {
             .1;
 
         let source = (
-            src_addr.0.unwrap_or("127.0.0.1"),
+            src_addr.0.unwrap_or(default_source),
-            src_addr
+            src_addr.1.parse::<u16>().context("Invalid source port")?,
-                .1
-                .parse::<u16>()
-                .with_context(|| "Invalid source port")?,
         )
             .to_socket_addrs()
-            .with_context(|| "Invalid source address")?
+            .context("Invalid source address")?
             .next()
-            .with_context(|| "Could not resolve source address")?;
+            .context("Could not resolve source address")?;
 
         let destination = (
             dst_addr.0,
-            dst_addr
+            dst_addr.1.parse::<u16>().context("Invalid source port")?,
-                .1
-                .parse::<u16>()
-                .with_context(|| "Invalid source port")?,
         )
             .to_socket_addrs() // TODO: Pass this as given and use DNS config instead (issue #15)
-            .with_context(|| "Invalid destination address")?
+            .context("Invalid destination address")?
             .next()
-            .with_context(|| "Could not resolve destination address")?;
+            .context("Could not resolve destination address")?;
 
         // Parse protocols
         let protocols = if let Some(protocols) = protocols {
@@ -363,7 +501,7 @@ impl PortForwardConfig {
         } else {
             Ok(vec![PortProtocol::Tcp])
         }
-        .with_context(|| "Failed to parse protocols")?;
+        .context("Failed to parse protocols")?;
 
         // Returns an config for each protocol
         Ok(protocols
@@ -372,6 +510,7 @@ impl PortForwardConfig {
                 source,
                 destination,
                 protocol,
+                remote: false,
             })
             .collect())
     }
@@ -379,13 +518,24 @@ impl PortForwardConfig {
 
 impl Display for PortForwardConfig {
     fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
+        if self.remote {
+            write!(
+                f,
+                "(remote){}:{}:{}",
+                self.source, self.destination, self.protocol
+            )
+        } else {
             write!(f, "{}:{}:{}", self.source, self.destination, self.protocol)
         }
+    }
 }
 
+/// Layer 7 protocols for ports.
 #[derive(Debug, Clone, Copy, Eq, PartialEq, Hash, Ord, PartialOrd)]
 pub enum PortProtocol {
+    /// TCP
     Tcp,
+    /// UDP
     Udp,
 }
 
@@ -424,18 +574,23 @@ mod tests {
     #[test]
     fn test_parse_port_forward_config_1() {
         assert_eq!(
-            PortForwardConfig::from_notation("192.168.0.1:8080:192.168.4.1:8081:TCP,UDP")
+            PortForwardConfig::from_notation(
+                "192.168.0.1:8080:192.168.4.1:8081:TCP,UDP",
+                DEFAULT_PORT_FORWARD_SOURCE
+            )
             .expect("Failed to parse"),
             vec![
                 PortForwardConfig {
                     source: SocketAddr::from_str("192.168.0.1:8080").unwrap(),
                     destination: SocketAddr::from_str("192.168.4.1:8081").unwrap(),
-                    protocol: PortProtocol::Tcp
+                    protocol: PortProtocol::Tcp,
+                    remote: false,
                 },
                 PortForwardConfig {
                     source: SocketAddr::from_str("192.168.0.1:8080").unwrap(),
                     destination: SocketAddr::from_str("192.168.4.1:8081").unwrap(),
-                    protocol: PortProtocol::Udp
+                    protocol: PortProtocol::Udp,
+                    remote: false,
                 }
             ]
         );
@@ -444,12 +599,16 @@ mod tests {
     #[test]
     fn test_parse_port_forward_config_2() {
         assert_eq!(
-            PortForwardConfig::from_notation("192.168.0.1:8080:192.168.4.1:8081:TCP")
+            PortForwardConfig::from_notation(
+                "192.168.0.1:8080:192.168.4.1:8081:TCP",
+                DEFAULT_PORT_FORWARD_SOURCE
+            )
             .expect("Failed to parse"),
             vec![PortForwardConfig {
                 source: SocketAddr::from_str("192.168.0.1:8080").unwrap(),
                 destination: SocketAddr::from_str("192.168.4.1:8081").unwrap(),
-                protocol: PortProtocol::Tcp
+                protocol: PortProtocol::Tcp,
+                remote: false,
             }]
         );
     }
@@ -457,12 +616,16 @@ mod tests {
     #[test]
     fn test_parse_port_forward_config_3() {
         assert_eq!(
-            PortForwardConfig::from_notation("0.0.0.0:8080:192.168.4.1:8081")
+            PortForwardConfig::from_notation(
+                "0.0.0.0:8080:192.168.4.1:8081",
+                DEFAULT_PORT_FORWARD_SOURCE
+            )
             .expect("Failed to parse"),
             vec![PortForwardConfig {
                 source: SocketAddr::from_str("0.0.0.0:8080").unwrap(),
                 destination: SocketAddr::from_str("192.168.4.1:8081").unwrap(),
-                protocol: PortProtocol::Tcp
+                protocol: PortProtocol::Tcp,
+                remote: false,
             }]
         );
     }
@@ -470,12 +633,16 @@ mod tests {
     #[test]
     fn test_parse_port_forward_config_4() {
         assert_eq!(
-            PortForwardConfig::from_notation("[::1]:8080:192.168.4.1:8081")
+            PortForwardConfig::from_notation(
+                "[::1]:8080:192.168.4.1:8081",
+                DEFAULT_PORT_FORWARD_SOURCE
+            )
             .expect("Failed to parse"),
             vec![PortForwardConfig {
                 source: SocketAddr::from_str("[::1]:8080").unwrap(),
                 destination: SocketAddr::from_str("192.168.4.1:8081").unwrap(),
-                protocol: PortProtocol::Tcp
+                protocol: PortProtocol::Tcp,
+                remote: false,
             }]
         );
     }
@@ -483,11 +650,13 @@ mod tests {
     #[test]
     fn test_parse_port_forward_config_5() {
         assert_eq!(
-            PortForwardConfig::from_notation("8080:192.168.4.1:8081").expect("Failed to parse"),
+            PortForwardConfig::from_notation("8080:192.168.4.1:8081", DEFAULT_PORT_FORWARD_SOURCE)
+                .expect("Failed to parse"),
             vec![PortForwardConfig {
                 source: SocketAddr::from_str("127.0.0.1:8080").unwrap(),
                 destination: SocketAddr::from_str("192.168.4.1:8081").unwrap(),
-                protocol: PortProtocol::Tcp
+                protocol: PortProtocol::Tcp,
+                remote: false,
             }]
         );
     }
@@ -495,11 +664,16 @@ mod tests {
     #[test]
     fn test_parse_port_forward_config_6() {
         assert_eq!(
-            PortForwardConfig::from_notation("8080:192.168.4.1:8081:TCP").expect("Failed to parse"),
+            PortForwardConfig::from_notation(
+                "8080:192.168.4.1:8081:TCP",
+                DEFAULT_PORT_FORWARD_SOURCE
+            )
+            .expect("Failed to parse"),
             vec![PortForwardConfig {
                 source: SocketAddr::from_str("127.0.0.1:8080").unwrap(),
                 destination: SocketAddr::from_str("192.168.4.1:8081").unwrap(),
-                protocol: PortProtocol::Tcp
+                protocol: PortProtocol::Tcp,
+                remote: false,
             }]
         );
     }
@@ -507,12 +681,16 @@ mod tests {
     #[test]
     fn test_parse_port_forward_config_7() {
         assert_eq!(
-            PortForwardConfig::from_notation("localhost:8080:192.168.4.1:8081")
+            PortForwardConfig::from_notation(
+                "localhost:8080:192.168.4.1:8081",
+                DEFAULT_PORT_FORWARD_SOURCE
+            )
             .expect("Failed to parse"),
             vec![PortForwardConfig {
                 source: "localhost:8080".to_socket_addrs().unwrap().next().unwrap(),
                 destination: SocketAddr::from_str("192.168.4.1:8081").unwrap(),
-                protocol: PortProtocol::Tcp
+                protocol: PortProtocol::Tcp,
+                remote: false,
             }]
         );
     }
@@ -520,12 +698,16 @@ mod tests {
     #[test]
     fn test_parse_port_forward_config_8() {
         assert_eq!(
-            PortForwardConfig::from_notation("localhost:8080:localhost:8081:TCP")
+            PortForwardConfig::from_notation(
+                "localhost:8080:localhost:8081:TCP",
+                DEFAULT_PORT_FORWARD_SOURCE
+            )
             .expect("Failed to parse"),
             vec![PortForwardConfig {
                 source: "localhost:8080".to_socket_addrs().unwrap().next().unwrap(),
                 destination: "localhost:8081".to_socket_addrs().unwrap().next().unwrap(),
-                protocol: PortProtocol::Tcp
+                protocol: PortProtocol::Tcp,
+                remote: false,
             }]
         );
     }

src/events.rs

@@ -0,0 +1,190 @@
+use bytes::Bytes;
+use std::fmt::{Display, Formatter};
+use std::sync::atomic::{AtomicU32, Ordering};
+use std::sync::Arc;
+
+use crate::config::PortForwardConfig;
+use crate::virtual_iface::VirtualPort;
+use crate::PortProtocol;
+
+/// Events that go on the bus between the local server, smoltcp, and WireGuard.
+#[derive(Debug, Clone)]
+pub enum Event {
+    /// Dumb event with no data.
+    Dumb,
+    /// A new connection with the local server was initiated, and the given virtual port was assigned.
+    ClientConnectionInitiated(PortForwardConfig, VirtualPort),
+    /// A connection was dropped from the pool and should be closed in all interfaces.
+    ClientConnectionDropped(VirtualPort),
+    /// Data received by the local server that should be sent to the virtual server.
+    LocalData(PortForwardConfig, VirtualPort, Bytes),
+    /// Data received by the remote server that should be sent to the local client.
+    RemoteData(VirtualPort, Bytes),
+    /// IP packet received from the WireGuard tunnel that should be passed through the corresponding virtual device.
+    InboundInternetPacket(PortProtocol, Bytes),
+    /// IP packet to be sent through the WireGuard tunnel as crafted by the virtual device.
+    OutboundInternetPacket(Bytes),
+    /// Notifies that a virtual device read an IP packet.
+    VirtualDeviceFed(PortProtocol),
+}
+
+impl Display for Event {
+    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
+        match self {
+            Event::Dumb => {
+                write!(f, "Dumb{{}}")
+            }
+            Event::ClientConnectionInitiated(pf, vp) => {
+                write!(f, "ClientConnectionInitiated{{ pf={} vp={} }}", pf, vp)
+            }
+            Event::ClientConnectionDropped(vp) => {
+                write!(f, "ClientConnectionDropped{{ vp={} }}", vp)
+            }
+            Event::LocalData(pf, vp, data) => {
+                let size = data.len();
+                write!(f, "LocalData{{ pf={} vp={} size={} }}", pf, vp, size)
+            }
+            Event::RemoteData(vp, data) => {
+                let size = data.len();
+                write!(f, "RemoteData{{ vp={} size={} }}", vp, size)
+            }
+            Event::InboundInternetPacket(proto, data) => {
+                let size = data.len();
+                write!(
+                    f,
+                    "InboundInternetPacket{{ proto={} size={} }}",
+                    proto, size
+                )
+            }
+            Event::OutboundInternetPacket(data) => {
+                let size = data.len();
+                write!(f, "OutboundInternetPacket{{ size={} }}", size)
+            }
+            Event::VirtualDeviceFed(proto) => {
+                write!(f, "VirtualDeviceFed{{ proto={} }}", proto)
+            }
+        }
+    }
+}
+
+#[derive(Clone)]
+pub struct Bus {
+    counter: Arc<AtomicU32>,
+    bus: Arc<tokio::sync::broadcast::Sender<(u32, Event)>>,
+}
+
+impl Bus {
+    /// Creates a new event bus.
+    pub fn new() -> Self {
+        let (bus, _) = tokio::sync::broadcast::channel(1000);
+        let bus = Arc::new(bus);
+        let counter = Arc::new(AtomicU32::default());
+        Self { bus, counter }
+    }
+
+    /// Creates a new endpoint on the event bus.
+    pub fn new_endpoint(&self) -> BusEndpoint {
+        let id = self.counter.fetch_add(1, Ordering::Relaxed);
+        let tx = (*self.bus).clone();
+        let rx = self.bus.subscribe();
+
+        let tx = BusSender { id, tx };
+        BusEndpoint { id, tx, rx }
+    }
+}
+
+impl Default for Bus {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+pub struct BusEndpoint {
+    id: u32,
+    tx: BusSender,
+    rx: tokio::sync::broadcast::Receiver<(u32, Event)>,
+}
+
+impl BusEndpoint {
+    /// Sends the event on the bus. Note that the messages sent by this endpoint won't reach itself.
+    pub fn send(&self, event: Event) {
+        self.tx.send(event)
+    }
+
+    /// Returns the unique sequential ID of this endpoint.
+    pub fn id(&self) -> u32 {
+        self.id
+    }
+
+    /// Awaits the next `Event` on the bus to be read.
+    pub async fn recv(&mut self) -> Event {
+        loop {
+            match self.rx.recv().await {
+                Ok((id, event)) => {
+                    if id == self.id {
+                        // If the event was sent by this endpoint, it is skipped
+                        continue;
+                    } else {
+                        return event;
+                    }
+                }
+                Err(_) => {
+                    error!("Failed to read event bus from endpoint #{}", self.id);
+                    return futures::future::pending().await;
+                }
+            }
+        }
+    }
+
+    /// Creates a new sender for this endpoint that can be cloned.
+    pub fn sender(&self) -> BusSender {
+        self.tx.clone()
+    }
+}
+
+#[derive(Clone)]
+pub struct BusSender {
+    id: u32,
+    tx: tokio::sync::broadcast::Sender<(u32, Event)>,
+}
+
+impl BusSender {
+    /// Sends the event on the bus. Note that the messages sent by this endpoint won't reach itself.
+    pub fn send(&self, event: Event) {
+        trace!("#{} -> {}", self.id, event);
+        match self.tx.send((self.id, event)) {
+            Ok(_) => {}
+            Err(_) => error!("Failed to send event to bus from endpoint #{}", self.id),
+        }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[tokio::test]
+    async fn test_bus() {
+        let bus = Bus::new();
+
+        let mut endpoint_1 = bus.new_endpoint();
+        let mut endpoint_2 = bus.new_endpoint();
+        let mut endpoint_3 = bus.new_endpoint();
+
+        assert_eq!(endpoint_1.id(), 0);
+        assert_eq!(endpoint_2.id(), 1);
+        assert_eq!(endpoint_3.id(), 2);
+
+        endpoint_1.send(Event::Dumb);
+        let recv_2 = endpoint_2.recv().await;
+        let recv_3 = endpoint_3.recv().await;
+        assert!(matches!(recv_2, Event::Dumb));
+        assert!(matches!(recv_3, Event::Dumb));
+
+        endpoint_2.send(Event::Dumb);
+        let recv_1 = endpoint_1.recv().await;
+        let recv_3 = endpoint_3.recv().await;
+        assert!(matches!(recv_1, Event::Dumb));
+        assert!(matches!(recv_3, Event::Dumb));
+    }
+}

src/ip_sink.rs

@@ -1,35 +0,0 @@
-use crate::virtual_device::VirtualIpDevice;
-use crate::wg::WireGuardTunnel;
-use smoltcp::iface::InterfaceBuilder;
-use std::sync::Arc;
-use tokio::time::Duration;
-
-/// A repeating task that processes unroutable IP packets.
-pub async fn run_ip_sink_interface(wg: Arc<WireGuardTunnel>) -> ! {
-    // Initialize interface
-    let device = VirtualIpDevice::new_sink(wg)
-        .await
-        .expect("Failed to initialize VirtualIpDevice for sink interface");
-
-    // No sockets on sink interface
-    let mut sockets: [_; 0] = Default::default();
-    let mut virtual_interface = InterfaceBuilder::new(device, &mut sockets[..])
-        .ip_addrs([])
-        .finalize();
-
-    loop {
-        let loop_start = smoltcp::time::Instant::now();
-        match virtual_interface.poll(loop_start) {
-            Ok(processed) if processed => {
-                trace!("[SINK] Virtual interface polled some packets to be processed",);
-                tokio::time::sleep(Duration::from_millis(1)).await;
-            }
-            Err(e) => {
-                error!("[SINK] Virtual interface poll error: {:?}", e);
-            }
-            _ => {
-                tokio::time::sleep(Duration::from_millis(5)).await;
-            }
-        }
-    }
-}

src/lib.rs

@@ -0,0 +1,122 @@
+#[macro_use]
+extern crate log;
+
+use std::sync::Arc;
+
+use anyhow::Context;
+
+use crate::config::{Config, PortProtocol};
+use crate::events::Bus;
+use crate::tunnel::tcp::TcpPortPool;
+use crate::tunnel::udp::UdpPortPool;
+use crate::virtual_device::VirtualIpDevice;
+use crate::virtual_iface::tcp::TcpVirtualInterface;
+use crate::virtual_iface::udp::UdpVirtualInterface;
+use crate::virtual_iface::VirtualInterfacePoll;
+use crate::wg::WireGuardTunnel;
+
+pub mod config;
+pub mod events;
+#[cfg(feature = "pcap")]
+pub mod pcap;
+pub mod tunnel;
+pub mod virtual_device;
+pub mod virtual_iface;
+pub mod wg;
+
+/// Starts the onetun tunnels in separate tokio tasks.
+///
+/// Note: This future completes immediately.
+pub async fn start_tunnels(config: Config, bus: Bus) -> anyhow::Result<()> {
+    // Initialize the port pool for each protocol
+    let tcp_port_pool = TcpPortPool::new();
+    let udp_port_pool = UdpPortPool::new();
+
+    #[cfg(feature = "pcap")]
+    if let Some(pcap_file) = config.pcap_file.clone() {
+        // Start packet capture
+        let bus = bus.clone();
+        tokio::spawn(async move { pcap::capture(pcap_file, bus).await });
+    }
+
+    let wg = WireGuardTunnel::new(&config, bus.clone())
+        .await
+        .context("Failed to initialize WireGuard tunnel")?;
+    let wg = Arc::new(wg);
+
+    {
+        // Start routine task for WireGuard
+        let wg = wg.clone();
+        tokio::spawn(async move { wg.routine_task().await });
+    }
+
+    {
+        // Start consumption task for WireGuard
+        let wg = wg.clone();
+        tokio::spawn(Box::pin(async move { wg.consume_task().await }));
+    }
+
+    {
+        // Start production task for WireGuard
+        let wg = wg.clone();
+        tokio::spawn(async move { wg.produce_task().await });
+    }
+
+    if config
+        .port_forwards
+        .iter()
+        .any(|pf| pf.protocol == PortProtocol::Tcp)
+    {
+        // TCP device
+        let bus = bus.clone();
+        let device =
+            VirtualIpDevice::new(PortProtocol::Tcp, bus.clone(), config.max_transmission_unit);
+
+        // Start TCP Virtual Interface
+        let port_forwards = config.port_forwards.clone();
+        let iface = TcpVirtualInterface::new(port_forwards, bus, config.source_peer_ip);
+        tokio::spawn(async move { iface.poll_loop(device).await });
+    }
+
+    if config
+        .port_forwards
+        .iter()
+        .any(|pf| pf.protocol == PortProtocol::Udp)
+    {
+        // UDP device
+        let bus = bus.clone();
+        let device =
+            VirtualIpDevice::new(PortProtocol::Udp, bus.clone(), config.max_transmission_unit);
+
+        // Start UDP Virtual Interface
+        let port_forwards = config.port_forwards.clone();
+        let iface = UdpVirtualInterface::new(port_forwards, bus, config.source_peer_ip);
+        tokio::spawn(async move { iface.poll_loop(device).await });
+    }
+
+    {
+        let port_forwards = config.port_forwards;
+        let source_peer_ip = config.source_peer_ip;
+
+        port_forwards
+            .into_iter()
+            .map(|pf| {
+                (
+                    pf,
+                    wg.clone(),
+                    tcp_port_pool.clone(),
+                    udp_port_pool.clone(),
+                    bus.clone(),
+                )
+            })
+            .for_each(move |(pf, wg, tcp_port_pool, udp_port_pool, bus)| {
+                tokio::spawn(async move {
+                    tunnel::port_forward(pf, source_peer_ip, tcp_port_pool, udp_port_pool, wg, bus)
+                        .await
+                        .unwrap_or_else(|e| error!("Port-forward failed for {} : {}", pf, e))
+                });
+            });
+    }
+
+    Ok(())
+}

src/main.rs

@@ -1,81 +1,36 @@
+#[cfg(feature = "bin")]
 #[macro_use]
 extern crate log;
 
-use std::sync::Arc;
+#[cfg(feature = "bin")]
-
-use anyhow::Context;
-
-use crate::config::Config;
-use crate::tunnel::tcp::TcpPortPool;
-use crate::tunnel::udp::UdpPortPool;
-use crate::wg::WireGuardTunnel;
-
-pub mod config;
-pub mod ip_sink;
-pub mod tunnel;
-pub mod virtual_device;
-pub mod virtual_iface;
-pub mod wg;
-
 #[tokio::main]
 async fn main() -> anyhow::Result<()> {
-    let config = Config::from_args().with_context(|| "Failed to read config")?;
+    use anyhow::Context;
+    use onetun::{config::Config, events::Bus};
+
+    let config = Config::from_args().context("Configuration has errors")?;
     init_logger(&config)?;
 
     for warning in &config.warnings {
         warn!("{}", warning);
     }
 
-    // Initialize the port pool for each protocol
+    let bus = Bus::default();
-    let tcp_port_pool = TcpPortPool::new();
+    onetun::start_tunnels(config, bus).await?;
-    let udp_port_pool = UdpPortPool::new();
-
-    let wg = WireGuardTunnel::new(&config)
-        .await
-        .with_context(|| "Failed to initialize WireGuard tunnel")?;
-    let wg = Arc::new(wg);
-
-    {
-        // Start routine task for WireGuard
-        let wg = wg.clone();
-        tokio::spawn(async move { wg.routine_task().await });
-    }
-
-    {
-        // Start consumption task for WireGuard
-        let wg = wg.clone();
-        tokio::spawn(async move { wg.consume_task().await });
-    }
-
-    {
-        // Start IP sink task for incoming IP packets
-        let wg = wg.clone();
-        tokio::spawn(async move { ip_sink::run_ip_sink_interface(wg).await });
-    }
-
-    {
-        let port_forwards = config.port_forwards;
-        let source_peer_ip = config.source_peer_ip;
-
-        port_forwards
-            .into_iter()
-            .map(|pf| (pf, wg.clone(), tcp_port_pool.clone(), udp_port_pool.clone()))
-            .for_each(move |(pf, wg, tcp_port_pool, udp_port_pool)| {
-                tokio::spawn(async move {
-                    tunnel::port_forward(pf, source_peer_ip, tcp_port_pool, udp_port_pool, wg)
-                        .await
-                        .unwrap_or_else(|e| error!("Port-forward failed for {} : {}", pf, e))
-                });
-            });
-    }
 
     futures::future::pending().await
 }
 
-fn init_logger(config: &Config) -> anyhow::Result<()> {
+#[cfg(not(feature = "bin"))]
-    let mut builder = pretty_env_logger::formatted_builder();
+fn main() -> anyhow::Result<()> {
-    builder.parse_filters(&config.log);
+    Err(anyhow::anyhow!("Binary compiled without 'bin' feature"))
-    builder
+}
-        .try_init()
+
-        .with_context(|| "Failed to initialize logger")
+#[cfg(feature = "bin")]
+fn init_logger(config: &onetun::config::Config) -> anyhow::Result<()> {
+    use anyhow::Context;
+
+    let mut builder = pretty_env_logger::formatted_timed_builder();
+    builder.parse_filters(&config.log);
+    builder.try_init().context("Failed to initialize logger")
 }

src/pcap.rs

@@ -0,0 +1,113 @@
+use crate::events::Event;
+use crate::Bus;
+use anyhow::Context;
+use smoltcp::time::Instant;
+use tokio::fs::File;
+use tokio::io::{AsyncWriteExt, BufWriter};
+
+struct Pcap {
+    writer: BufWriter<File>,
+}
+
+/// libpcap file writer
+/// This is mostly taken from `smoltcp`, but rewritten to be async.
+impl Pcap {
+    async fn flush(&mut self) -> anyhow::Result<()> {
+        self.writer
+            .flush()
+            .await
+            .context("Failed to flush pcap writer")
+    }
+
+    async fn write(&mut self, data: &[u8]) -> anyhow::Result<usize> {
+        self.writer
+            .write(data)
+            .await
+            .with_context(|| format!("Failed to write {} bytes to pcap writer", data.len()))
+    }
+
+    async fn write_u16(&mut self, value: u16) -> anyhow::Result<()> {
+        self.writer
+            .write_u16(value)
+            .await
+            .context("Failed to write u16 to pcap writer")
+    }
+
+    async fn write_u32(&mut self, value: u32) -> anyhow::Result<()> {
+        self.writer
+            .write_u32(value)
+            .await
+            .context("Failed to write u32 to pcap writer")
+    }
+
+    async fn global_header(&mut self) -> anyhow::Result<()> {
+        self.write_u32(0xa1b2c3d4).await?; // magic number
+        self.write_u16(2).await?; // major version
+        self.write_u16(4).await?; // minor version
+        self.write_u32(0).await?; // timezone (= UTC)
+        self.write_u32(0).await?; // accuracy (not used)
+        self.write_u32(65535).await?; // maximum packet length
+        self.write_u32(101).await?; // link-layer header type (101 = IP)
+        self.flush().await
+    }
+
+    async fn packet_header(&mut self, timestamp: Instant, length: usize) -> anyhow::Result<()> {
+        assert!(length <= 65535);
+
+        self.write_u32(timestamp.secs() as u32).await?; // timestamp seconds
+        self.write_u32(timestamp.micros() as u32).await?; // timestamp microseconds
+        self.write_u32(length as u32).await?; // captured length
+        self.write_u32(length as u32).await?; // original length
+        Ok(())
+    }
+
+    async fn packet(&mut self, timestamp: Instant, packet: &[u8]) -> anyhow::Result<()> {
+        self.packet_header(timestamp, packet.len())
+            .await
+            .context("Failed to write packet header to pcap writer")?;
+        self.write(packet)
+            .await
+            .context("Failed to write packet to pcap writer")?;
+        self.writer
+            .flush()
+            .await
+            .context("Failed to flush pcap writer")?;
+        self.flush().await
+    }
+}
+
+/// Listens on the event bus for IP packets sent from and to the WireGuard tunnel.
+pub async fn capture(pcap_file: String, bus: Bus) -> anyhow::Result<()> {
+    let mut endpoint = bus.new_endpoint();
+    let file = File::create(&pcap_file)
+        .await
+        .context("Failed to create pcap file")?;
+    let writer = BufWriter::new(file);
+
+    let mut writer = Pcap { writer };
+    writer
+        .global_header()
+        .await
+        .context("Failed to write global header to pcap writer")?;
+
+    info!("Capturing WireGuard IP packets to {}", &pcap_file);
+    loop {
+        match endpoint.recv().await {
+            Event::InboundInternetPacket(_proto, ip) => {
+                let instant = Instant::now();
+                writer
+                    .packet(instant, &ip)
+                    .await
+                    .context("Failed to write inbound IP packet to pcap writer")?;
+            }
+            Event::OutboundInternetPacket(ip) => {
+                let instant = Instant::now();
+                writer
+                    .packet(instant, &ip)
+                    .await
+                    .context("Failed to write output IP packet to pcap writer")?;
+            }
+            _ => {}
+        }
+    }
+}

src/tunnel/mod.rs

@@ -2,12 +2,12 @@ use std::net::IpAddr;
 use std::sync::Arc;
 
 use crate::config::{PortForwardConfig, PortProtocol};
+use crate::events::Bus;
 use crate::tunnel::tcp::TcpPortPool;
 use crate::tunnel::udp::UdpPortPool;
 use crate::wg::WireGuardTunnel;
 
 pub mod tcp;
-#[allow(unused)]
 pub mod udp;
 
 pub async fn port_forward(
@@ -16,6 +16,7 @@ pub async fn port_forward(
     tcp_port_pool: TcpPortPool,
     udp_port_pool: UdpPortPool,
     wg: Arc<WireGuardTunnel>,
+    bus: Bus,
 ) -> anyhow::Result<()> {
     info!(
         "Tunneling {} [{}]->[{}] (via [{}] as peer {})",
@@ -27,7 +28,7 @@ pub async fn port_forward(
     );
 
     match port_forward.protocol {
-        PortProtocol::Tcp => tcp::tcp_proxy_server(port_forward, tcp_port_pool, wg).await,
+        PortProtocol::Tcp => tcp::tcp_proxy_server(port_forward, tcp_port_pool, bus).await,
-        PortProtocol::Udp => udp::udp_proxy_server(port_forward, udp_port_pool, wg).await,
+        PortProtocol::Udp => udp::udp_proxy_server(port_forward, udp_port_pool, bus).await,
     }
 }

src/tunnel/tcp.rs

@@ -1,17 +1,18 @@
-use crate::config::{PortForwardConfig, PortProtocol};
-use crate::virtual_iface::tcp::TcpVirtualInterface;
-use crate::virtual_iface::{VirtualInterfacePoll, VirtualPort};
-use crate::wg::WireGuardTunnel;
-use anyhow::Context;
 use std::collections::VecDeque;
-use std::sync::atomic::{AtomicBool, Ordering};
-use std::sync::Arc;
-use tokio::net::{TcpListener, TcpStream};
-
 use std::ops::Range;
+use std::sync::Arc;
+use std::time::Duration;
 
+use anyhow::Context;
+use bytes::BytesMut;
 use rand::seq::SliceRandom;
 use rand::thread_rng;
+use tokio::io::AsyncWriteExt;
+use tokio::net::{TcpListener, TcpStream};
+
+use crate::config::{PortForwardConfig, PortProtocol};
+use crate::events::{Bus, Event};
+use crate::virtual_iface::VirtualPort;
 
 const MAX_PACKET: usize = 65536;
 const MIN_PORT: u16 = 1000;
@@ -22,19 +23,18 @@ const PORT_RANGE: Range<u16> = MIN_PORT..MAX_PORT;
 pub async fn tcp_proxy_server(
     port_forward: PortForwardConfig,
     port_pool: TcpPortPool,
-    wg: Arc<WireGuardTunnel>,
+    bus: Bus,
 ) -> anyhow::Result<()> {
     let listener = TcpListener::bind(port_forward.source)
         .await
-        .with_context(|| "Failed to listen on TCP proxy server")?;
+        .context("Failed to listen on TCP proxy server")?;
 
     loop {
-        let wg = wg.clone();
         let port_pool = port_pool.clone();
         let (socket, peer_addr) = listener
             .accept()
             .await
-            .with_context(|| "Failed to accept connection on TCP proxy server")?;
+            .context("Failed to accept connection on TCP proxy server")?;
 
         // Assign a 'virtual port': this is a unique port number used to route IP packets
         // received from the WireGuard tunnel. It is the port number that the virtual client will
@@ -52,10 +52,10 @@ pub async fn tcp_proxy_server(
 
         info!("[{}] Incoming connection from {}", virtual_port, peer_addr);
 
+        let bus = bus.clone();
         tokio::spawn(async move {
             let port_pool = port_pool.clone();
-            let result =
+            let result = handle_tcp_proxy_connection(socket, virtual_port, port_forward, bus).await;
-                handle_tcp_proxy_connection(socket, virtual_port, port_forward, wg.clone()).await;
 
             if let Err(e) = result {
                 error!(
@@ -66,8 +66,7 @@ pub async fn tcp_proxy_server(
                 info!("[{}] Connection closed by client", virtual_port);
             }
 
-            // Release port when connection drops
+            tokio::time::sleep(Duration::from_millis(100)).await; // Make sure the other tasks have time to process the event
-            wg.release_virtual_interface(VirtualPort(virtual_port, PortProtocol::Tcp));
             port_pool.release(virtual_port).await;
         });
     }
@@ -75,72 +74,26 @@ pub async fn tcp_proxy_server(
 
 /// Handles a new TCP connection with its assigned virtual port.
 async fn handle_tcp_proxy_connection(
-    socket: TcpStream,
+    mut socket: TcpStream,
-    virtual_port: u16,
+    virtual_port: VirtualPort,
     port_forward: PortForwardConfig,
-    wg: Arc<WireGuardTunnel>,
+    bus: Bus,
 ) -> anyhow::Result<()> {
-    // Abort signal for stopping the Virtual Interface
+    let mut endpoint = bus.new_endpoint();
-    let abort = Arc::new(AtomicBool::new(false));
+    endpoint.send(Event::ClientConnectionInitiated(port_forward, virtual_port));
-
-    // Signals that the Virtual Client is ready to send data
-    let (virtual_client_ready_tx, virtual_client_ready_rx) = tokio::sync::oneshot::channel::<()>();
-
-    // data_to_real_client_(tx/rx): This task reads the data from this mpsc channel to send back
-    // to the real client.
-    let (data_to_real_client_tx, mut data_to_real_client_rx) = tokio::sync::mpsc::channel(1_000);
-
-    // data_to_real_server_(tx/rx): This task sends the data received from the real client to the
-    // virtual interface (virtual server socket).
-    let (data_to_virtual_server_tx, data_to_virtual_server_rx) = tokio::sync::mpsc::channel(1_000);
-
-    // Spawn virtual interface
-    {
-        let abort = abort.clone();
-        let virtual_interface = TcpVirtualInterface::new(
-            virtual_port,
-            port_forward,
-            wg,
-            abort.clone(),
-            data_to_real_client_tx,
-            data_to_virtual_server_rx,
-            virtual_client_ready_tx,
-        );
-
-        tokio::spawn(async move {
-            virtual_interface.poll_loop().await.unwrap_or_else(|e| {
-                error!("Virtual interface poll loop failed unexpectedly: {}", e);
-                abort.store(true, Ordering::Relaxed);
-            })
-        });
-    }
-
-    // Wait for virtual client to be ready.
-    virtual_client_ready_rx
-        .await
-        .with_context(|| "Virtual client dropped before being ready.")?;
-    trace!("[{}] Virtual client is ready to send data", virtual_port);
 
+    let mut buffer = BytesMut::with_capacity(MAX_PACKET);
     loop {
         tokio::select! {
             readable_result = socket.readable() => {
                 match readable_result {
                     Ok(_) => {
-                        // Buffer for the individual TCP segment.
-                        let mut buffer = Vec::with_capacity(MAX_PACKET);
                         match socket.try_read_buf(&mut buffer) {
                             Ok(size) if size > 0 => {
-                                let data = &buffer[..size];
+                                let data = Vec::from(&buffer[..size]);
-                                debug!(
+                                endpoint.send(Event::LocalData(port_forward, virtual_port, data.into()));
-                                    "[{}] Read {} bytes of TCP data from real client",
+                                // Reset buffer
-                                    virtual_port, size
+                                buffer.clear();
-                                );
-                                if let Err(e) = data_to_virtual_server_tx.send(data.to_vec()).await {
-                                    error!(
-                                        "[{}] Failed to dispatch data to virtual interface: {:?}",
-                                        virtual_port, e
-                                    );
-                                }
                             }
                             Err(ref e) if e.kind() == std::io::ErrorKind::WouldBlock => {
                                 continue;
@@ -163,43 +116,47 @@ async fn handle_tcp_proxy_connection(
                     }
                 }
             }
-            data_recv_result = data_to_real_client_rx.recv() => {
+            event = endpoint.recv() => {
-                match data_recv_result {
+                match event {
-                    Some(data) => match socket.try_write(&data) {
+                    Event::ClientConnectionDropped(e_vp) if e_vp == virtual_port => {
-                        Ok(size) => {
+                        // This connection is supposed to be closed, stop the task.
-                            debug!(
-                                "[{}] Wrote {} bytes of TCP data to real client",
-                                virtual_port, size
-                            );
-                        }
-                        Err(ref e) if e.kind() == std::io::ErrorKind::WouldBlock => {
-                            if abort.load(Ordering::Relaxed) {
                         break;
-                            } else {
-                                continue;
                     }
+                    Event::RemoteData(e_vp, data) if e_vp == virtual_port => {
+                        // Have remote data to send to the local client
+                        if let Err(e) = socket.writable().await {
+                            error!("[{}] Failed to check if writable: {:?}", virtual_port, e);
                         }
+                        let expected = data.len();
+                        let mut sent = 0;
+                        loop {
+                            if sent >= expected {
+                                break;
+                            }
+                            match socket.write(&data[sent..expected]).await {
+                                Ok(written) => {
+                                    debug!("[{}] Sent {} (expected {}) bytes to local client", virtual_port, written, expected);
+                                    sent += written;
+                                    if sent < expected {
+                                        debug!("[{}] Will try to resend remaining {} bytes to local client", virtual_port, (expected - written));
+                                    }
+                                },
                                 Err(e) => {
-                            error!(
+                                    error!("[{}] Failed to send {} bytes to local client: {:?}", virtual_port, expected, e);
-                                "[{}] Failed to write to client TCP socket: {:?}",
-                                virtual_port, e
-                            );
-                        }
-                    },
-                    None => {
-                        if abort.load(Ordering::Relaxed) {
                                     break;
-                        } else {
-                            continue;
                                 }
-                    },
+                            }
+                        }
+                    }
+                    _ => {}
                 }
             }
         }
     }
 
-    trace!("[{}] TCP socket handler task terminated", virtual_port);
+    // Notify other endpoints that this task has closed and no more data is to be sent to the local client
-    abort.store(true, Ordering::Relaxed);
+    endpoint.send(Event::ClientConnectionDropped(virtual_port));
+
     Ok(())
 }
 
@@ -229,20 +186,20 @@ impl TcpPortPool {
         }
     }
 
-    /// Requests a free port from the pool. An error is returned if none is available (exhaused max capacity).
+    /// Requests a free port from the pool. An error is returned if none is available (exhausted max capacity).
-    pub async fn next(&self) -> anyhow::Result<u16> {
+    pub async fn next(&self) -> anyhow::Result<VirtualPort> {
         let mut inner = self.inner.write().await;
         let port = inner
             .queue
             .pop_front()
-            .with_context(|| "TCP virtual port pool is exhausted")?;
+            .context("TCP virtual port pool is exhausted")?;
-        Ok(port)
+        Ok(VirtualPort::new(port, PortProtocol::Tcp))
     }
 
     /// Releases a port back into the pool.
-    pub async fn release(&self, port: u16) {
+    pub async fn release(&self, port: VirtualPort) {
         let mut inner = self.inner.write().await;
-        inner.queue.push_back(port);
+        inner.queue.push_back(port.num());
     }
 }
 

src/tunnel/udp.rs

@@ -1,21 +1,19 @@
-use std::collections::{BTreeMap, HashMap, VecDeque};
+use std::collections::{HashMap, VecDeque};
 use std::net::{IpAddr, SocketAddr};
 use std::ops::Range;
-use std::sync::atomic::{AtomicBool, Ordering};
 use std::sync::Arc;
 use std::time::Instant;
 
 use anyhow::Context;
+use bytes::Bytes;
 use priority_queue::double_priority_queue::DoublePriorityQueue;
-use priority_queue::priority_queue::PriorityQueue;
 use rand::seq::SliceRandom;
 use rand::thread_rng;
 use tokio::net::UdpSocket;
 
 use crate::config::{PortForwardConfig, PortProtocol};
-use crate::virtual_iface::udp::UdpVirtualInterface;
+use crate::events::{Bus, Event};
-use crate::virtual_iface::{VirtualInterfacePoll, VirtualPort};
+use crate::virtual_iface::VirtualPort;
-use crate::wg::WireGuardTunnel;
 
 const MAX_PACKET: usize = 65536;
 const MIN_PORT: u16 = 1000;
@@ -30,61 +28,24 @@ const UDP_TIMEOUT_SECONDS: u64 = 60;
 /// TODO: Make this configurable by the CLI
 const PORTS_PER_IP: usize = 100;
 
+/// Starts the server that listens on UDP datagrams.
 pub async fn udp_proxy_server(
     port_forward: PortForwardConfig,
     port_pool: UdpPortPool,
-    wg: Arc<WireGuardTunnel>,
+    bus: Bus,
 ) -> anyhow::Result<()> {
-    // Abort signal
+    let mut endpoint = bus.new_endpoint();
-    let abort = Arc::new(AtomicBool::new(false));
-
-    // data_to_real_client_(tx/rx): This task reads the data from this mpsc channel to send back
-    // to the real client.
-    let (data_to_real_client_tx, mut data_to_real_client_rx) =
-        tokio::sync::mpsc::channel::<(VirtualPort, Vec<u8>)>(1_000);
-
-    // data_to_real_server_(tx/rx): This task sends the data received from the real client to the
-    // virtual interface (virtual server socket).
-    let (data_to_virtual_server_tx, data_to_virtual_server_rx) =
-        tokio::sync::mpsc::channel::<(VirtualPort, Vec<u8>)>(1_000);
-
-    {
-        // Spawn virtual interface
-        // Note: contrary to TCP, there is only one UDP virtual interface
-        let virtual_interface = UdpVirtualInterface::new(
-            port_forward,
-            wg,
-            data_to_real_client_tx,
-            data_to_virtual_server_rx,
-        );
-        let abort = abort.clone();
-        tokio::spawn(async move {
-            virtual_interface.poll_loop().await.unwrap_or_else(|e| {
-                error!("Virtual interface poll loop failed unexpectedly: {}", e);
-                abort.store(true, Ordering::Relaxed);
-            });
-        });
-    }
-
     let socket = UdpSocket::bind(port_forward.source)
         .await
-        .with_context(|| "Failed to bind on UDP proxy address")?;
+        .context("Failed to bind on UDP proxy address")?;
 
     let mut buffer = [0u8; MAX_PACKET];
     loop {
-        if abort.load(Ordering::Relaxed) {
-            break;
-        }
         tokio::select! {
             to_send_result = next_udp_datagram(&socket, &mut buffer, port_pool.clone()) => {
                 match to_send_result {
                     Ok(Some((port, data))) => {
-                        data_to_virtual_server_tx.send((port, data)).await.unwrap_or_else(|e| {
+                        endpoint.send(Event::LocalData(port_forward, port, data));
-                            error!(
-                                "Failed to dispatch data to UDP virtual interface: {:?}",
-                                e
-                            );
-                        });
                     }
                     Ok(None) => {
                         continue;
@@ -98,18 +59,34 @@ pub async fn udp_proxy_server(
                     }
                 }
             }
-            data_recv_result = data_to_real_client_rx.recv() => {
+            event = endpoint.recv() => {
-                if let Some((port, data)) = data_recv_result {
+                if let Event::RemoteData(virtual_port, data) = event {
-                    if let Some(peer_addr) = port_pool.get_peer_addr(port.0).await {
+                    if let Some(peer) = port_pool.get_peer_addr(virtual_port).await {
-                        if let Err(e) = socket.send_to(&data, peer_addr).await {
+                        // Have remote data to send to the local client
-                            error!(
+                        if let Err(e) = socket.writable().await {
-                                "[{}] Failed to send UDP datagram to real client ({}): {:?}",
+                            error!("[{}] Failed to check if writable: {:?}", virtual_port, e);
-                                port,
-                                peer_addr,
-                                e,
-                            );
                         }
-                        port_pool.update_last_transmit(port.0).await;
+                        let expected = data.len();
+                        let mut sent = 0;
+                        loop {
+                            if sent >= expected {
+                                break;
+                            }
+                            match socket.send_to(&data[sent..expected], peer).await {
+                                Ok(written) => {
+                                    debug!("[{}] Sent {} (expected {}) bytes to local client", virtual_port, written, expected);
+                                    sent += written;
+                                    if sent < expected {
+                                        debug!("[{}] Will try to resend remaining {} bytes to local client", virtual_port, (expected - written));
+                                    }
+                                },
+                                Err(e) => {
+                                    error!("[{}] Failed to send {} bytes to local client: {:?}", virtual_port, expected, e);
+                                    break;
+                                }
+                            }
+                        }
+                        port_pool.update_last_transmit(virtual_port).await;
                     }
                 }
             }
@@ -122,11 +99,11 @@ async fn next_udp_datagram(
     socket: &UdpSocket,
     buffer: &mut [u8],
     port_pool: UdpPortPool,
-) -> anyhow::Result<Option<(VirtualPort, Vec<u8>)>> {
+) -> anyhow::Result<Option<(VirtualPort, Bytes)>> {
     let (size, peer_addr) = socket
         .recv_from(buffer)
         .await
-        .with_context(|| "Failed to accept incoming UDP datagram")?;
+        .context("Failed to accept incoming UDP datagram")?;
 
     // Assign a 'virtual port': this is a unique port number used to route IP packets
     // received from the WireGuard tunnel. It is the port number that the virtual client will
@@ -141,17 +118,16 @@ async fn next_udp_datagram(
             return Ok(None);
         }
     };
-    let port = VirtualPort(port, PortProtocol::Udp);
 
     debug!(
         "[{}] Received datagram of {} bytes from {}",
         port, size, peer_addr
     );
 
-    port_pool.update_last_transmit(port.0).await;
+    port_pool.update_last_transmit(port).await;
 
     let data = buffer[..size].to_vec();
-    Ok(Some((port, data)))
+    Ok(Some((port, data.into())))
 }
 
 /// A pool of virtual ports available for TCP connections.
@@ -181,14 +157,14 @@ impl UdpPortPool {
     }
 
     /// Requests a free port from the pool. An error is returned if none is available (exhausted max capacity).
-    pub async fn next(&self, peer_addr: SocketAddr) -> anyhow::Result<u16> {
+    pub async fn next(&self, peer_addr: SocketAddr) -> anyhow::Result<VirtualPort> {
         // A port found to be reused. This is outside of the block because the read lock cannot be upgraded to a write lock.
         let mut port_reuse: Option<u16> = None;
 
         {
             let inner = self.inner.read().await;
             if let Some(port) = inner.port_by_peer_addr.get(&peer_addr) {
-                return Ok(*port);
+                return Ok(VirtualPort::new(*port, PortProtocol::Udp));
             }
 
             // Count how many ports are being used by the peer IP
@@ -236,30 +212,30 @@ impl UdpPortPool {
                     None
                 }
             })
-            .with_context(|| "virtual port pool is exhausted")?;
+            .context("Virtual port pool is exhausted")?;
 
         inner.port_by_peer_addr.insert(peer_addr, port);
         inner.peer_addr_by_port.insert(port, peer_addr);
-        Ok(port)
+        Ok(VirtualPort::new(port, PortProtocol::Udp))
     }
 
     /// Notify that the given virtual port has received or transmitted a UDP datagram.
-    pub async fn update_last_transmit(&self, port: u16) {
+    pub async fn update_last_transmit(&self, port: VirtualPort) {
         let mut inner = self.inner.write().await;
-        if let Some(peer) = inner.peer_addr_by_port.get(&port).copied() {
+        if let Some(peer) = inner.peer_addr_by_port.get(&port.num()).copied() {
-            let mut pq: &mut DoublePriorityQueue<u16, Instant> = inner
+            let pq: &mut DoublePriorityQueue<u16, Instant> = inner
                 .peer_port_usage
                 .entry(peer.ip())
                 .or_insert_with(Default::default);
-            pq.push(port, Instant::now());
+            pq.push(port.num(), Instant::now());
         }
-        let mut pq: &mut DoublePriorityQueue<u16, Instant> = &mut inner.port_usage;
+        let pq: &mut DoublePriorityQueue<u16, Instant> = &mut inner.port_usage;
-        pq.push(port, Instant::now());
+        pq.push(port.num(), Instant::now());
     }
 
-    pub async fn get_peer_addr(&self, port: u16) -> Option<SocketAddr> {
+    pub async fn get_peer_addr(&self, port: VirtualPort) -> Option<SocketAddr> {
         let inner = self.inner.read().await;
-        inner.peer_addr_by_port.get(&port).copied()
+        inner.peer_addr_by_port.get(&port.num()).copied()
     }
 }
 

src/virtual_device.rs

@@ -1,116 +1,136 @@
-use crate::virtual_iface::VirtualPort;
+use crate::config::PortProtocol;
-use crate::wg::{WireGuardTunnel, DISPATCH_CAPACITY};
+use crate::events::{BusSender, Event};
-use anyhow::Context;
+use crate::Bus;
-use smoltcp::phy::{Device, DeviceCapabilities, Medium};
+use bytes::{BufMut, Bytes, BytesMut};
-use smoltcp::time::Instant;
+use smoltcp::{
-use std::sync::Arc;
+    phy::{DeviceCapabilities, Medium},
+    time::Instant,
+};
+use std::{
+    collections::VecDeque,
+    sync::{Arc, Mutex},
+};
 
-/// The max transmission unit for WireGuard.
+/// A virtual device that processes IP packets through smoltcp and WireGuard.
-const WG_MTU: usize = 1420;
-
-/// A virtual device that processes IP packets. IP packets received from the WireGuard endpoint
-/// are made available to this device using a channel receiver. IP packets sent from this device
-/// are asynchronously sent out to the WireGuard tunnel.
 pub struct VirtualIpDevice {
-    /// Tunnel to send IP packets to.
+    /// Max transmission unit (bytes)
-    wg: Arc<WireGuardTunnel>,
+    max_transmission_unit: usize,
     /// Channel receiver for received IP packets.
-    ip_dispatch_rx: tokio::sync::mpsc::Receiver<Vec<u8>>,
+    bus_sender: BusSender,
+    /// Local queue for packets received from the bus that need to go through the smoltcp interface.
+    process_queue: Arc<Mutex<VecDeque<Bytes>>>,
 }
 
 impl VirtualIpDevice {
     /// Initializes a new virtual IP device.
-    pub fn new(
+    pub fn new(protocol: PortProtocol, bus: Bus, max_transmission_unit: usize) -> Self {
-        wg: Arc<WireGuardTunnel>,
+        let mut bus_endpoint = bus.new_endpoint();
-        ip_dispatch_rx: tokio::sync::mpsc::Receiver<Vec<u8>>,
+        let bus_sender = bus_endpoint.sender();
-    ) -> Self {
+        let process_queue = Arc::new(Mutex::new(VecDeque::new()));
-        Self { wg, ip_dispatch_rx }
+
+        {
+            let process_queue = process_queue.clone();
+            tokio::spawn(async move {
+                loop {
+                    match bus_endpoint.recv().await {
+                        Event::InboundInternetPacket(ip_proto, data) if ip_proto == protocol => {
+                            let mut queue = process_queue
+                                .lock()
+                                .expect("Failed to acquire process queue lock");
+                            queue.push_back(data);
+                            bus_endpoint.send(Event::VirtualDeviceFed(ip_proto));
+                        }
+                        _ => {}
+                    }
+                }
+            });
         }
 
-    /// Registers a virtual IP device for a single virtual client.
+        Self {
-    pub fn new_direct(virtual_port: VirtualPort, wg: Arc<WireGuardTunnel>) -> anyhow::Result<Self> {
+            bus_sender,
-        let (ip_dispatch_tx, ip_dispatch_rx) = tokio::sync::mpsc::channel(DISPATCH_CAPACITY);
+            process_queue,
-
+            max_transmission_unit,
-        wg.register_virtual_interface(virtual_port, ip_dispatch_tx)
-            .with_context(|| "Failed to register IP dispatch for virtual interface")?;
-
-        Ok(Self { wg, ip_dispatch_rx })
         }
-
-    pub async fn new_sink(wg: Arc<WireGuardTunnel>) -> anyhow::Result<Self> {
-        let ip_dispatch_rx = wg
-            .register_sink_interface()
-            .await
-            .with_context(|| "Failed to register IP dispatch for sink virtual interface")?;
-        Ok(Self { wg, ip_dispatch_rx })
     }
 }
 
-impl<'a> Device<'a> for VirtualIpDevice {
+impl smoltcp::phy::Device for VirtualIpDevice {
-    type RxToken = RxToken;
+    type RxToken<'a>
-    type TxToken = TxToken;
+        = RxToken
+    where
+        Self: 'a;
+    type TxToken<'a>
+        = TxToken
+    where
+        Self: 'a;
 
-    fn receive(&'a mut self) -> Option<(Self::RxToken, Self::TxToken)> {
+    fn receive(&mut self, _timestamp: Instant) -> Option<(Self::RxToken<'_>, Self::TxToken<'_>)> {
-        match self.ip_dispatch_rx.try_recv() {
+        let next = {
-            Ok(buffer) => Some((
+            let mut queue = self
-                Self::RxToken { buffer },
+                .process_queue
+                .lock()
+                .expect("Failed to acquire process queue lock");
+            queue.pop_front()
+        };
+        match next {
+            Some(buffer) => Some((
+                Self::RxToken {
+                    buffer: {
+                        let mut buf = BytesMut::new();
+                        buf.put(buffer);
+                        buf
+                    },
+                },
                 Self::TxToken {
-                    wg: self.wg.clone(),
+                    sender: self.bus_sender.clone(),
                 },
             )),
-            Err(_) => None,
+            None => None,
         }
     }
 
-    fn transmit(&'a mut self) -> Option<Self::TxToken> {
+    fn transmit(&mut self, _timestamp: Instant) -> Option<Self::TxToken<'_>> {
         Some(TxToken {
-            wg: self.wg.clone(),
+            sender: self.bus_sender.clone(),
         })
     }
 
     fn capabilities(&self) -> DeviceCapabilities {
         let mut cap = DeviceCapabilities::default();
         cap.medium = Medium::Ip;
-        cap.max_transmission_unit = WG_MTU;
+        cap.max_transmission_unit = self.max_transmission_unit;
         cap
     }
 }
 
 #[doc(hidden)]
 pub struct RxToken {
-    buffer: Vec<u8>,
+    buffer: BytesMut,
 }
 
 impl smoltcp::phy::RxToken for RxToken {
-    fn consume<R, F>(mut self, _timestamp: Instant, f: F) -> smoltcp::Result<R>
+    fn consume<R, F>(self, f: F) -> R
     where
-        F: FnOnce(&mut [u8]) -> smoltcp::Result<R>,
+        F: FnOnce(&[u8]) -> R,
     {
-        f(&mut self.buffer)
+        f(&self.buffer)
     }
 }
 
 #[doc(hidden)]
 pub struct TxToken {
-    wg: Arc<WireGuardTunnel>,
+    sender: BusSender,
 }
 
 impl smoltcp::phy::TxToken for TxToken {
-    fn consume<R, F>(self, _timestamp: Instant, len: usize, f: F) -> smoltcp::Result<R>
+    fn consume<R, F>(self, len: usize, f: F) -> R
     where
-        F: FnOnce(&mut [u8]) -> smoltcp::Result<R>,
+        F: FnOnce(&mut [u8]) -> R,
     {
-        let mut buffer = Vec::new();
+        let mut buffer = vec![0; len];
-        buffer.resize(len, 0);
         let result = f(&mut buffer);
-        tokio::spawn(async move {
+        self.sender
-            match self.wg.send_ip_packet(&buffer).await {
+            .send(Event::OutboundInternetPacket(buffer.into()));
-                Ok(_) => {}
-                Err(e) => {
-                    error!("Failed to send IP packet to WireGuard endpoint: {:?}", e);
-                }
-            }
-        });
         result
     }
 }

src/virtual_iface/mod.rs

@@ -2,6 +2,7 @@ pub mod tcp;
 pub mod udp;
 
 use crate::config::PortProtocol;
+use crate::VirtualIpDevice;
 use async_trait::async_trait;
 use std::fmt::{Display, Formatter};
 
@@ -9,15 +10,56 @@ use std::fmt::{Display, Formatter};
 pub trait VirtualInterfacePoll {
     /// Initializes the virtual interface and processes incoming data to be dispatched
     /// to the WireGuard tunnel and to the real client.
-    async fn poll_loop(mut self) -> anyhow::Result<()>;
+    async fn poll_loop(mut self, device: VirtualIpDevice) -> anyhow::Result<()>;
 }
 
 /// Virtual port.
 #[derive(Copy, Clone, Debug, Hash, Eq, PartialEq, Ord, PartialOrd)]
-pub struct VirtualPort(pub u16, pub PortProtocol);
+pub struct VirtualPort(u16, PortProtocol);
+
+impl VirtualPort {
+    /// Create a new `VirtualPort` instance, with the given port number and associated protocol.
+    pub fn new(port: u16, proto: PortProtocol) -> Self {
+        VirtualPort(port, proto)
+    }
+
+    /// The port number
+    pub fn num(&self) -> u16 {
+        self.0
+    }
+
+    /// The protocol of this port.
+    pub fn proto(&self) -> PortProtocol {
+        self.1
+    }
+}
+
+impl From<VirtualPort> for u16 {
+    fn from(port: VirtualPort) -> Self {
+        port.num()
+    }
+}
+
+impl From<&VirtualPort> for u16 {
+    fn from(port: &VirtualPort) -> Self {
+        port.num()
+    }
+}
+
+impl From<VirtualPort> for PortProtocol {
+    fn from(port: VirtualPort) -> Self {
+        port.proto()
+    }
+}
+
+impl From<&VirtualPort> for PortProtocol {
+    fn from(port: &VirtualPort) -> Self {
+        port.proto()
+    }
+}
 
 impl Display for VirtualPort {
     fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
-        write!(f, "[{}:{}]", self.0, self.1)
+        write!(f, "[{}:{}]", self.num(), self.proto())
     }
 }

src/virtual_iface/tcp.rs

@@ -1,284 +1,257 @@
 use crate::config::{PortForwardConfig, PortProtocol};
+use crate::events::Event;
 use crate::virtual_device::VirtualIpDevice;
 use crate::virtual_iface::{VirtualInterfacePoll, VirtualPort};
-use crate::wg::WireGuardTunnel;
+use crate::Bus;
 use anyhow::Context;
 use async_trait::async_trait;
-use smoltcp::iface::InterfaceBuilder;
+use bytes::Bytes;
-use smoltcp::socket::{TcpSocket, TcpSocketBuffer, TcpState};
+use smoltcp::iface::PollResult;
-use smoltcp::wire::{IpAddress, IpCidr};
+use smoltcp::{
-use std::sync::atomic::{AtomicBool, Ordering};
+    iface::{Config, Interface, SocketHandle, SocketSet},
-use std::sync::Arc;
+    socket::tcp,
-use std::time::Duration;
+    time::Instant,
+    wire::{HardwareAddress, IpAddress, IpCidr, IpVersion},
+};
+use std::{
+    collections::{HashMap, HashSet, VecDeque},
+    net::IpAddr,
+    time::Duration,
+};
 
 const MAX_PACKET: usize = 65536;
 
 /// A virtual interface for proxying Layer 7 data to Layer 3 packets, and vice-versa.
 pub struct TcpVirtualInterface {
-    /// The virtual port assigned to the virtual client, used to
+    source_peer_ip: IpAddr,
-    /// route Layer 4 segments/datagrams to and from the WireGuard tunnel.
+    port_forwards: Vec<PortForwardConfig>,
-    virtual_port: u16,
+    bus: Bus,
-    /// The overall port-forward configuration: used for the destination address (on which
+    sockets: SocketSet<'static>,
-    /// the virtual server listens) and the protocol in use.
-    port_forward: PortForwardConfig,
-    /// The WireGuard tunnel to send IP packets to.
-    wg: Arc<WireGuardTunnel>,
-    /// Abort signal to shutdown the virtual interface and its parent task.
-    abort: Arc<AtomicBool>,
-    /// Channel sender for pushing Layer 7 data back to the real client.
-    data_to_real_client_tx: tokio::sync::mpsc::Sender<Vec<u8>>,
-    /// Channel receiver for processing Layer 7 data through the virtual interface.
-    data_to_virtual_server_rx: tokio::sync::mpsc::Receiver<Vec<u8>>,
-    /// One-shot sender to notify the parent task that the virtual client is ready to send Layer 7 data.
-    virtual_client_ready_tx: tokio::sync::oneshot::Sender<()>,
 }
 
 impl TcpVirtualInterface {
     /// Initialize the parameters for a new virtual interface.
     /// Use the `poll_loop()` future to start the virtual interface poll loop.
-    pub fn new(
+    pub fn new(port_forwards: Vec<PortForwardConfig>, bus: Bus, source_peer_ip: IpAddr) -> Self {
-        virtual_port: u16,
-        port_forward: PortForwardConfig,
-        wg: Arc<WireGuardTunnel>,
-        abort: Arc<AtomicBool>,
-        data_to_real_client_tx: tokio::sync::mpsc::Sender<Vec<u8>>,
-        data_to_virtual_server_rx: tokio::sync::mpsc::Receiver<Vec<u8>>,
-        virtual_client_ready_tx: tokio::sync::oneshot::Sender<()>,
-    ) -> Self {
         Self {
-            virtual_port,
+            port_forwards: port_forwards
-            port_forward,
+                .into_iter()
-            wg,
+                .filter(|f| matches!(f.protocol, PortProtocol::Tcp))
-            abort,
+                .collect(),
-            data_to_real_client_tx,
+            source_peer_ip,
-            data_to_virtual_server_rx,
+            bus,
-            virtual_client_ready_tx,
+            sockets: SocketSet::new([]),
         }
     }
+
+    fn new_server_socket(port_forward: PortForwardConfig) -> anyhow::Result<tcp::Socket<'static>> {
+        static mut TCP_SERVER_RX_DATA: [u8; 0] = [];
+        static mut TCP_SERVER_TX_DATA: [u8; 0] = [];
+
+        let tcp_rx_buffer = tcp::SocketBuffer::new(unsafe { &mut TCP_SERVER_RX_DATA[..] });
+        let tcp_tx_buffer = tcp::SocketBuffer::new(unsafe { &mut TCP_SERVER_TX_DATA[..] });
+        let mut socket = tcp::Socket::new(tcp_rx_buffer, tcp_tx_buffer);
+
+        socket
+            .listen((
+                IpAddress::from(port_forward.destination.ip()),
+                port_forward.destination.port(),
+            ))
+            .context("Virtual server socket failed to listen")?;
+
+        Ok(socket)
+    }
+
+    fn new_client_socket() -> anyhow::Result<tcp::Socket<'static>> {
+        let rx_data = vec![0u8; MAX_PACKET];
+        let tx_data = vec![0u8; MAX_PACKET];
+        let tcp_rx_buffer = tcp::SocketBuffer::new(rx_data);
+        let tcp_tx_buffer = tcp::SocketBuffer::new(tx_data);
+        let socket = tcp::Socket::new(tcp_rx_buffer, tcp_tx_buffer);
+        Ok(socket)
+    }
+
+    fn addresses(&self) -> Vec<IpCidr> {
+        let mut addresses = HashSet::new();
+        addresses.insert(IpAddress::from(self.source_peer_ip));
+        for config in self.port_forwards.iter() {
+            addresses.insert(IpAddress::from(config.destination.ip()));
+        }
+        addresses
+            .into_iter()
+            .map(|addr| IpCidr::new(addr, addr_length(&addr)))
+            .collect()
+    }
 }
 
 #[async_trait]
 impl VirtualInterfacePoll for TcpVirtualInterface {
-    async fn poll_loop(self) -> anyhow::Result<()> {
+    async fn poll_loop(mut self, mut device: VirtualIpDevice) -> anyhow::Result<()> {
-        let mut virtual_client_ready_tx = Some(self.virtual_client_ready_tx);
+        // Create CIDR block for source peer IP + each port forward IP
-        let mut data_to_virtual_server_rx = self.data_to_virtual_server_rx;
+        let addresses = self.addresses();
-        let source_peer_ip = self.wg.source_peer_ip;
+        let config = Config::new(HardwareAddress::Ip);
 
-        // Create a device and interface to simulate IP packets
+        // Create virtual interface (contains smoltcp state machine)
-        // In essence:
+        let mut iface = Interface::new(config, &mut device, Instant::now());
-        // * TCP packets received from the 'real' client are 'sent' to the 'virtual server' via the 'virtual client'
+        iface.update_ip_addrs(|ip_addrs| {
-        // * Those TCP packets generate IP packets, which are captured from the interface and sent to the WireGuardTunnel
+            addresses.into_iter().for_each(|addr| {
-        // * IP packets received by the WireGuardTunnel (from the endpoint) are fed into this 'virtual interface'
+                ip_addrs
-        // * The interface processes those IP packets and routes them to the 'virtual client' (the rest is discarded)
+                    .push(addr)
-        // * The TCP data read by the 'virtual client' is sent to the 'real' TCP client
+                    .expect("maximum number of IPs in TCP interface reached");
+            });
+        });
 
-        // Consumer for IP packets to send through the virtual interface
+        // Create virtual server for each port forward
-        // Initialize the interface
+        for port_forward in self.port_forwards.iter() {
-        let device =
+            let server_socket = TcpVirtualInterface::new_server_socket(*port_forward)?;
-            VirtualIpDevice::new_direct(VirtualPort(self.virtual_port, PortProtocol::Tcp), self.wg)
+            self.sockets.add(server_socket);
-                .with_context(|| "Failed to initialize TCP VirtualIpDevice")?;
-
-        // there are always 2 sockets: 1 virtual client and 1 virtual server.
-        let mut sockets: [_; 2] = Default::default();
-        let mut virtual_interface = InterfaceBuilder::new(device, &mut sockets[..])
-            .ip_addrs([
-                // Interface handles IP packets for the sender and recipient
-                IpCidr::new(IpAddress::from(source_peer_ip), 32),
-                IpCidr::new(IpAddress::from(self.port_forward.destination.ip()), 32),
-            ])
-            .finalize();
-
-        // Server socket: this is a placeholder for the interface to route new connections to.
-        let server_socket: anyhow::Result<TcpSocket> = {
-            static mut TCP_SERVER_RX_DATA: [u8; 0] = [];
-            static mut TCP_SERVER_TX_DATA: [u8; 0] = [];
-            let tcp_rx_buffer = TcpSocketBuffer::new(unsafe { &mut TCP_SERVER_RX_DATA[..] });
-            let tcp_tx_buffer = TcpSocketBuffer::new(unsafe { &mut TCP_SERVER_TX_DATA[..] });
-            let mut socket = TcpSocket::new(tcp_rx_buffer, tcp_tx_buffer);
-
-            socket
-                .listen((
-                    IpAddress::from(self.port_forward.destination.ip()),
-                    self.port_forward.destination.port(),
-                ))
-                .with_context(|| "Virtual server socket failed to listen")?;
-
-            Ok(socket)
-        };
-
-        let client_socket: anyhow::Result<TcpSocket> = {
-            let rx_data = vec![0u8; MAX_PACKET];
-            let tx_data = vec![0u8; MAX_PACKET];
-            let tcp_rx_buffer = TcpSocketBuffer::new(rx_data);
-            let tcp_tx_buffer = TcpSocketBuffer::new(tx_data);
-            let socket = TcpSocket::new(tcp_rx_buffer, tcp_tx_buffer);
-            Ok(socket)
-        };
-
-        let _server_handle = virtual_interface.add_socket(server_socket?);
-        let client_handle = virtual_interface.add_socket(client_socket?);
-
-        // Any data that wasn't sent because it was over the sending buffer limit
-        let mut tx_extra = Vec::new();
-
-        // Counts the connection attempts by the virtual client
-        let mut connection_attempts = 0;
-        // Whether the client has successfully connected before. Prevents the case of connecting again.
-        let mut has_connected = false;
-
-        loop {
-            let loop_start = smoltcp::time::Instant::now();
-
-            // Shutdown occurs when the real client closes the connection,
-            // or if the client was in a CLOSE-WAIT state (after a server FIN) and had no data to send anymore.
-            // One last poll-loop iteration is executed so that the RST segment can be dispatched.
-            let shutdown = self.abort.load(Ordering::Relaxed);
-
-            if shutdown {
-                // Shutdown: sends a RST packet.
-                trace!("[{}] Shutting down virtual interface", self.virtual_port);
-                let client_socket = virtual_interface.get_socket::<TcpSocket>(client_handle);
-                client_socket.abort();
         }
 
-            match virtual_interface.poll(loop_start) {
+        // The next time to poll the interface. Can be None for instant poll.
-                Ok(processed) if processed => {
+        let mut next_poll: Option<tokio::time::Instant> = None;
-                    trace!(
+
-                        "[{}] Virtual interface polled some packets to be processed",
+        // Bus endpoint to read events
-                        self.virtual_port
+        let mut endpoint = self.bus.new_endpoint();
-                    );
+
+        // Maps virtual port to its client socket handle
+        let mut port_client_handle_map: HashMap<VirtualPort, SocketHandle> = HashMap::new();
+
+        // Data packets to send from a virtual client
+        let mut send_queue: HashMap<VirtualPort, VecDeque<Bytes>> = HashMap::new();
+
+        loop {
+            tokio::select! {
+                _ = match (next_poll, port_client_handle_map.len()) {
+                    (None, 0) => tokio::time::sleep(Duration::MAX),
+                    (None, _) => tokio::time::sleep(Duration::ZERO),
+                    (Some(until), _) => tokio::time::sleep_until(until),
+                } => {
+                    let loop_start = smoltcp::time::Instant::now();
+
+                    // Find closed sockets
+                    port_client_handle_map.retain(|virtual_port, client_handle| {
+                        let client_socket = self.sockets.get_mut::<tcp::Socket>(*client_handle);
+                        if client_socket.state() == tcp::State::Closed {
+                            endpoint.send(Event::ClientConnectionDropped(*virtual_port));
+                            send_queue.remove(virtual_port);
+                            self.sockets.remove(*client_handle);
+                            false
+                        } else {
+                            // Not closed, retain
+                            true
+                        }
+                    });
+
+                    if iface.poll(loop_start, &mut device, &mut self.sockets) == PollResult::SocketStateChanged {
+                        log::trace!("TCP virtual interface polled some packets to be processed");
+                    }
+
+                    for (virtual_port, client_handle) in port_client_handle_map.iter() {
+                        let client_socket = self.sockets.get_mut::<tcp::Socket>(*client_handle);
+                        if client_socket.can_send() {
+                            if let Some(send_queue) = send_queue.get_mut(virtual_port) {
+                                let to_transfer = send_queue.pop_front();
+                                if let Some(to_transfer_slice) = to_transfer.as_deref() {
+                                    let total = to_transfer_slice.len();
+                                    match client_socket.send_slice(to_transfer_slice) {
+                                        Ok(sent) => {
+                                            if sent < total {
+                                                // Sometimes only a subset is sent, so the rest needs to be sent on the next poll
+                                                let tx_extra = Vec::from(&to_transfer_slice[sent..total]);
+                                                send_queue.push_front(tx_extra.into());
+                                            }
                                         }
                                         Err(e) => {
                                             error!(
-                        "[{}] Virtual interface poll error: {:?}",
+                                                "Failed to send slice via virtual client socket: {:?}", e
-                        self.virtual_port, e
                                             );
                                         }
-                _ => {}
+                                    }
+                                } else if client_socket.state() == tcp::State::CloseWait {
+                                    client_socket.close();
+                                }
+                            }
+                        }
+                        if client_socket.can_recv() {
+                            match client_socket.recv(|buffer| (buffer.len(), Bytes::from(buffer.to_vec()))) {
+                                Ok(data) => {
+                                    debug!("[{}] Received {} bytes from virtual server", virtual_port, data.len());
+                                    if !data.is_empty() {
+                                        endpoint.send(Event::RemoteData(*virtual_port, data));
+                                    }
+                                }
+                                Err(e) => {
+                                    error!(
+                                        "Failed to read from virtual client socket: {:?}", e
+                                    );
+                                }
+                            }
+                        }
                     }
 
-            {
+                    // The virtual interface determines the next time to poll (this is to reduce unnecessary polls)
-                let (client_socket, context) =
+                    next_poll = match iface.poll_delay(loop_start, &self.sockets) {
-                    virtual_interface.get_socket_and_context::<TcpSocket>(client_handle);
+                        Some(smoltcp::time::Duration::ZERO) => None,
+                        Some(delay) => {
+                            trace!("TCP Virtual interface delayed next poll by {}", delay);
+                            Some(tokio::time::Instant::now() + Duration::from_millis(delay.total_millis()))
+                        },
+                        None => None,
+                    };
+                }
+                event = endpoint.recv() => {
+                    match event {
+                        Event::ClientConnectionInitiated(port_forward, virtual_port) => {
+                            let client_socket = TcpVirtualInterface::new_client_socket()?;
+                            let client_handle = self.sockets.add(client_socket);
+
+                            // Add handle to map
+                            port_client_handle_map.insert(virtual_port, client_handle);
+                            send_queue.insert(virtual_port, VecDeque::new());
+
+                            let client_socket = self.sockets.get_mut::<tcp::Socket>(client_handle);
+                            let context = iface.context();
 
-                if !shutdown && client_socket.state() == TcpState::Closed && !has_connected {
-                    // Not shutting down, but the client socket is closed, and the client never successfully connected.
-                    if connection_attempts < 10 {
-                        // Try to connect
                             client_socket
                                 .connect(
                                     context,
                                     (
-                                    IpAddress::from(self.port_forward.destination.ip()),
+                                        IpAddress::from(port_forward.destination.ip()),
-                                    self.port_forward.destination.port(),
+                                        port_forward.destination.port(),
                                     ),
-                                (IpAddress::from(source_peer_ip), self.virtual_port),
+                                    (IpAddress::from(self.source_peer_ip), virtual_port.num()),
                                 )
-                            .with_context(|| "Virtual server socket failed to listen")?;
+                                .context("Virtual server socket failed to listen")?;
-                        if connection_attempts > 0 {
-                            debug!(
-                                "[{}] Virtual client retrying connection in 500ms",
-                                self.virtual_port
-                            );
-                            // Not our first connection attempt, wait a little bit.
-                            tokio::time::sleep(Duration::from_millis(500)).await;
-                        }
-                    } else {
-                        // Too many connection attempts
-                        self.abort.store(true, Ordering::Relaxed);
-                    }
-                    connection_attempts += 1;
-                    continue;
-                }
 
-                if client_socket.state() == TcpState::Established {
+                            next_poll = None;
-                    // Prevent reconnection if the server later closes.
-                    has_connected = true;
                         }
-
+                        Event::ClientConnectionDropped(virtual_port) => {
-                if client_socket.can_recv() {
+                            if let Some(client_handle) = port_client_handle_map.get(&virtual_port) {
-                    match client_socket.recv(|buffer| (buffer.len(), buffer.to_vec())) {
+                                let client_socket = self.sockets.get_mut::<tcp::Socket>(*client_handle);
-                        Ok(data) => {
+                                client_socket.close();
-                            trace!(
+                                next_poll = None;
-                                "[{}] Virtual client received {} bytes of data",
-                                self.virtual_port,
-                                data.len()
-                            );
-                            // Send it to the real client
-                            if let Err(e) = self.data_to_real_client_tx.send(data).await {
-                                error!("[{}] Failed to dispatch data from virtual client to real client: {:?}", self.virtual_port, e);
                             }
                         }
-                        Err(e) => {
+                        Event::LocalData(_, virtual_port, data) if send_queue.contains_key(&virtual_port) => {
-                            error!(
+                            if let Some(send_queue) = send_queue.get_mut(&virtual_port) {
-                                "[{}] Failed to read from virtual client socket: {:?}",
+                                send_queue.push_back(data);
-                                self.virtual_port, e
+                                next_poll = None;
-                            );
                             }
                         }
+                        Event::VirtualDeviceFed(PortProtocol::Tcp) => {
+                            next_poll = None;
                         }
-                if client_socket.can_send() {
+                        _ => {}
-                    if let Some(virtual_client_ready_tx) = virtual_client_ready_tx.take() {
-                        virtual_client_ready_tx
-                            .send(())
-                            .expect("Failed to notify real client that virtual client is ready");
-                    }
-
-                    let mut to_transfer = None;
-
-                    if tx_extra.is_empty() {
-                        // The payload segment from the previous loop is complete,
-                        // we can now read the next payload in the queue.
-                        if let Ok(data) = data_to_virtual_server_rx.try_recv() {
-                            to_transfer = Some(data);
-                        } else if client_socket.state() == TcpState::CloseWait {
-                            // No data to be sent in this loop. If the client state is CLOSE-WAIT (because of a server FIN),
-                            // the interface is shutdown.
-                            trace!("[{}] Shutting down virtual interface because client sent no more data, and server sent FIN (CLOSE-WAIT)", self.virtual_port);
-                            self.abort.store(true, Ordering::Relaxed);
-                            continue;
-                        }
-                    }
-
-                    let to_transfer_slice = to_transfer.as_ref().unwrap_or(&tx_extra).as_slice();
-                    if !to_transfer_slice.is_empty() {
-                        let total = to_transfer_slice.len();
-                        match client_socket.send_slice(to_transfer_slice) {
-                            Ok(sent) => {
-                                trace!(
-                                    "[{}] Sent {}/{} bytes via virtual client socket",
-                                    self.virtual_port,
-                                    sent,
-                                    total,
-                                );
-                                tx_extra = Vec::from(&to_transfer_slice[sent..total]);
-                            }
-                            Err(e) => {
-                                error!(
-                                    "[{}] Failed to send slice via virtual client socket: {:?}",
-                                    self.virtual_port, e
-                                );
                     }
                 }
             }
         }
     }
-
+}
-            if shutdown {
+
-                break;
+const fn addr_length(addr: &IpAddress) -> u8 {
-            }
+    match addr.version() {
-
+        IpVersion::Ipv4 => 32,
-            match virtual_interface.poll_delay(loop_start) {
+        IpVersion::Ipv6 => 128,
-                Some(smoltcp::time::Duration::ZERO) => {
+    }
-                    continue;
-                }
-                _ => {
-                    tokio::time::sleep(Duration::from_millis(1)).await;
-                }
-            }
-        }
-        trace!("[{}] Virtual interface task terminated", self.virtual_port);
-        self.abort.store(true, Ordering::Relaxed);
-        Ok(())
-    }
 }

src/virtual_iface/udp.rs

@@ -1,200 +1,227 @@
-use anyhow::Context;
-use std::collections::HashMap;
-use std::sync::Arc;
-use std::time::Duration;
-
-use async_trait::async_trait;
-use smoltcp::iface::{InterfaceBuilder, SocketHandle};
-use smoltcp::socket::{UdpPacketMetadata, UdpSocket, UdpSocketBuffer};
-use smoltcp::wire::{IpAddress, IpCidr};
-
 use crate::config::PortForwardConfig;
+use crate::events::Event;
 use crate::virtual_device::VirtualIpDevice;
 use crate::virtual_iface::{VirtualInterfacePoll, VirtualPort};
-use crate::wg::{WireGuardTunnel, DISPATCH_CAPACITY};
+use crate::{Bus, PortProtocol};
+use anyhow::Context;
+use async_trait::async_trait;
+use bytes::Bytes;
+use smoltcp::iface::PollResult;
+use smoltcp::{
+    iface::{Config, Interface, SocketHandle, SocketSet},
+    socket::udp::{self, UdpMetadata},
+    time::Instant,
+    wire::{HardwareAddress, IpAddress, IpCidr, IpVersion},
+};
+use std::{
+    collections::{HashMap, HashSet, VecDeque},
+    net::IpAddr,
+    time::Duration,
+};
 
 const MAX_PACKET: usize = 65536;
 
 pub struct UdpVirtualInterface {
-    port_forward: PortForwardConfig,
+    source_peer_ip: IpAddr,
-    wg: Arc<WireGuardTunnel>,
+    port_forwards: Vec<PortForwardConfig>,
-    data_to_real_client_tx: tokio::sync::mpsc::Sender<(VirtualPort, Vec<u8>)>,
+    bus: Bus,
-    data_to_virtual_server_rx: tokio::sync::mpsc::Receiver<(VirtualPort, Vec<u8>)>,
+    sockets: SocketSet<'static>,
 }
 
 impl UdpVirtualInterface {
-    pub fn new(
+    /// Initialize the parameters for a new virtual interface.
-        port_forward: PortForwardConfig,
+    /// Use the `poll_loop()` future to start the virtual interface poll loop.
-        wg: Arc<WireGuardTunnel>,
+    pub fn new(port_forwards: Vec<PortForwardConfig>, bus: Bus, source_peer_ip: IpAddr) -> Self {
-        data_to_real_client_tx: tokio::sync::mpsc::Sender<(VirtualPort, Vec<u8>)>,
-        data_to_virtual_server_rx: tokio::sync::mpsc::Receiver<(VirtualPort, Vec<u8>)>,
-    ) -> Self {
         Self {
-            port_forward,
+            port_forwards: port_forwards
-            wg,
+                .into_iter()
-            data_to_real_client_tx,
+                .filter(|f| matches!(f.protocol, PortProtocol::Udp))
-            data_to_virtual_server_rx,
+                .collect(),
+            source_peer_ip,
+            bus,
+            sockets: SocketSet::new([]),
         }
     }
+
+    fn new_server_socket(port_forward: PortForwardConfig) -> anyhow::Result<udp::Socket<'static>> {
+        static mut UDP_SERVER_RX_META: [udp::PacketMetadata; 0] = [];
+        static mut UDP_SERVER_RX_DATA: [u8; 0] = [];
+        static mut UDP_SERVER_TX_META: [udp::PacketMetadata; 0] = [];
+        static mut UDP_SERVER_TX_DATA: [u8; 0] = [];
+        let udp_rx_buffer =
+            udp::PacketBuffer::new(unsafe { &mut UDP_SERVER_RX_META[..] }, unsafe {
+                &mut UDP_SERVER_RX_DATA[..]
+            });
+        let udp_tx_buffer =
+            udp::PacketBuffer::new(unsafe { &mut UDP_SERVER_TX_META[..] }, unsafe {
+                &mut UDP_SERVER_TX_DATA[..]
+            });
+        let mut socket = udp::Socket::new(udp_rx_buffer, udp_tx_buffer);
+        socket
+            .bind((
+                IpAddress::from(port_forward.destination.ip()),
+                port_forward.destination.port(),
+            ))
+            .context("UDP virtual server socket failed to bind")?;
+        Ok(socket)
+    }
+
+    fn new_client_socket(
+        source_peer_ip: IpAddr,
+        client_port: VirtualPort,
+    ) -> anyhow::Result<udp::Socket<'static>> {
+        let rx_meta = vec![udp::PacketMetadata::EMPTY; 10];
+        let tx_meta = vec![udp::PacketMetadata::EMPTY; 10];
+        let rx_data = vec![0u8; MAX_PACKET];
+        let tx_data = vec![0u8; MAX_PACKET];
+        let udp_rx_buffer = udp::PacketBuffer::new(rx_meta, rx_data);
+        let udp_tx_buffer = udp::PacketBuffer::new(tx_meta, tx_data);
+        let mut socket = udp::Socket::new(udp_rx_buffer, udp_tx_buffer);
+        socket
+            .bind((IpAddress::from(source_peer_ip), client_port.num()))
+            .context("UDP virtual client failed to bind")?;
+        Ok(socket)
+    }
+
+    fn addresses(&self) -> Vec<IpCidr> {
+        let mut addresses = HashSet::new();
+        addresses.insert(IpAddress::from(self.source_peer_ip));
+        for config in self.port_forwards.iter() {
+            addresses.insert(IpAddress::from(config.destination.ip()));
+        }
+        addresses
+            .into_iter()
+            .map(|addr| IpCidr::new(addr, addr_length(&addr)))
+            .collect()
+    }
 }
 
 #[async_trait]
 impl VirtualInterfacePoll for UdpVirtualInterface {
-    async fn poll_loop(self) -> anyhow::Result<()> {
+    async fn poll_loop(mut self, mut device: VirtualIpDevice) -> anyhow::Result<()> {
-        // Data receiver to dispatch using virtual client sockets
+        // Create CIDR block for source peer IP + each port forward IP
-        let mut data_to_virtual_server_rx = self.data_to_virtual_server_rx;
+        let addresses = self.addresses();
+        let config = Config::new(HardwareAddress::Ip);
 
-        // The IP to bind client sockets to
+        // Create virtual interface (contains smoltcp state machine)
-        let source_peer_ip = self.wg.source_peer_ip;
+        let mut iface = Interface::new(config, &mut device, Instant::now());
-
+        iface.update_ip_addrs(|ip_addrs| {
-        // The IP/port to bind the server socket to
+            addresses.into_iter().for_each(|addr| {
-        let destination = self.port_forward.destination;
+                ip_addrs
-
+                    .push(addr)
-        // Initialize a channel for IP packets.
+                    .expect("maximum number of IPs in UDP interface reached");
-        // The "base transmitted" is cloned so that each virtual port can register a sender in the tunnel.
-        // The receiver is given to the device so that the Virtual Interface can process incoming IP packets from the tunnel.
-        let (base_ip_dispatch_tx, ip_dispatch_rx) = tokio::sync::mpsc::channel(DISPATCH_CAPACITY);
-
-        let device = VirtualIpDevice::new(self.wg.clone(), ip_dispatch_rx);
-        let mut virtual_interface = InterfaceBuilder::new(device, vec![])
-            .ip_addrs([
-                // Interface handles IP packets for the sender and recipient
-                IpCidr::new(source_peer_ip.into(), 32),
-                IpCidr::new(destination.ip().into(), 32),
-            ])
-            .finalize();
-
-        // Server socket: this is a placeholder for the interface.
-        let server_socket: anyhow::Result<UdpSocket> = {
-            static mut UDP_SERVER_RX_META: [UdpPacketMetadata; 0] = [];
-            static mut UDP_SERVER_RX_DATA: [u8; 0] = [];
-            static mut UDP_SERVER_TX_META: [UdpPacketMetadata; 0] = [];
-            static mut UDP_SERVER_TX_DATA: [u8; 0] = [];
-            let udp_rx_buffer =
-                UdpSocketBuffer::new(unsafe { &mut UDP_SERVER_RX_META[..] }, unsafe {
-                    &mut UDP_SERVER_RX_DATA[..]
             });
-            let udp_tx_buffer =
-                UdpSocketBuffer::new(unsafe { &mut UDP_SERVER_TX_META[..] }, unsafe {
-                    &mut UDP_SERVER_TX_DATA[..]
         });
-            let mut socket = UdpSocket::new(udp_rx_buffer, udp_tx_buffer);
 
-            socket
+        // Create virtual server for each port forward
-                .bind((IpAddress::from(destination.ip()), destination.port()))
+        for port_forward in self.port_forwards.iter() {
-                .with_context(|| "UDP virtual server socket failed to listen")?;
+            let server_socket = UdpVirtualInterface::new_server_socket(*port_forward)?;
+            self.sockets.add(server_socket);
+        }
 
-            Ok(socket)
+        // The next time to poll the interface. Can be None for instant poll.
-        };
-
-        let _server_handle = virtual_interface.add_socket(server_socket?);
-
-        // A map of virtual port to client socket.
-        let mut client_sockets: HashMap<VirtualPort, SocketHandle> = HashMap::new();
-
-        // The next instant required to poll the virtual interface
-        // None means "immediate poll required".
         let mut next_poll: Option<tokio::time::Instant> = None;
 
+        // Bus endpoint to read events
+        let mut endpoint = self.bus.new_endpoint();
+
+        // Maps virtual port to its client socket handle
+        let mut port_client_handle_map: HashMap<VirtualPort, SocketHandle> = HashMap::new();
+
+        // Data packets to send from a virtual client
+        let mut send_queue: HashMap<VirtualPort, VecDeque<(PortForwardConfig, Bytes)>> =
+            HashMap::new();
+
         loop {
-            let wg = self.wg.clone();
             tokio::select! {
-                // Wait the recommended amount of time by smoltcp, and poll again.
+                _ = match (next_poll, port_client_handle_map.len()) {
-                _ = match next_poll {
+                    (None, 0) => tokio::time::sleep(Duration::MAX),
-                    None => tokio::time::sleep(Duration::ZERO),
+                    (None, _) => tokio::time::sleep(Duration::ZERO),
-                    Some(until) => tokio::time::sleep_until(until)
+                    (Some(until), _) => tokio::time::sleep_until(until),
                 } => {
                     let loop_start = smoltcp::time::Instant::now();
 
-                    match virtual_interface.poll(loop_start) {
+                    if iface.poll(loop_start, &mut device, &mut self.sockets) == PollResult::SocketStateChanged {
-                        Ok(processed) if processed => {
+                        log::trace!("UDP virtual interface polled some packets to be processed");
-                            trace!("UDP virtual interface polled some packets to be processed");
-                        }
-                        Err(e) => error!("UDP virtual interface poll error: {:?}", e),
-                        _ => {}
                     }
 
-                    // Loop through each client socket and check if there is any data to send back
+                    for (virtual_port, client_handle) in port_client_handle_map.iter() {
-                    // to the real client.
+                        let client_socket = self.sockets.get_mut::<udp::Socket>(*client_handle);
-                    for (virtual_port, client_socket_handle) in client_sockets.iter() {
+                        if client_socket.can_send() {
-                        let client_socket = virtual_interface.get_socket::<UdpSocket>(*client_socket_handle);
+                            if let Some(send_queue) = send_queue.get_mut(virtual_port) {
-                        match client_socket.recv() {
+                                let to_transfer = send_queue.pop_front();
-                            Ok((data, _peer)) => {
+                                if let Some((port_forward, data)) = to_transfer {
-                                // Send the data back to the real client using MPSC channel
-                                self.data_to_real_client_tx
-                                    .send((*virtual_port, data.to_vec()))
-                                    .await
-                                    .unwrap_or_else(|e| {
-                                        error!(
-                                            "[{}] Failed to dispatch data from virtual client to real client: {:?}",
-                                            virtual_port, e
-                                        );
-                                    });
-                            }
-                            Err(smoltcp::Error::Exhausted) => {}
-                            Err(e) => {
-                                error!(
-                                    "[{}] Failed to read from virtual client socket: {:?}",
-                                    virtual_port, e
-                                );
-                            }
-                        }
-                    }
-
-                    next_poll = match virtual_interface.poll_delay(loop_start) {
-                        Some(smoltcp::time::Duration::ZERO) => None,
-                        Some(delay) => Some(tokio::time::Instant::now() + Duration::from_millis(delay.millis())),
-                        None => None,
-                    }
-                }
-                // Wait for data to be received from the real client
-                data_recv_result = data_to_virtual_server_rx.recv() => {
-                    if let Some((client_port, data)) = data_recv_result {
-                        // Register the socket in WireGuard Tunnel (overrides any previous registration as well)
-                        wg.register_virtual_interface(client_port, base_ip_dispatch_tx.clone())
-                            .unwrap_or_else(|e| {
-                                error!(
-                                    "[{}] Failed to register UDP socket in WireGuard tunnel: {:?}",
-                                    client_port, e
-                                );
-                            });
-
-                        let client_socket_handle = client_sockets.entry(client_port).or_insert_with(|| {
-                            let rx_meta = vec![UdpPacketMetadata::EMPTY; 10];
-                            let tx_meta = vec![UdpPacketMetadata::EMPTY; 10];
-                            let rx_data = vec![0u8; MAX_PACKET];
-                            let tx_data = vec![0u8; MAX_PACKET];
-                            let udp_rx_buffer = UdpSocketBuffer::new(rx_meta, rx_data);
-                            let udp_tx_buffer = UdpSocketBuffer::new(tx_meta, tx_data);
-                            let mut socket = UdpSocket::new(udp_rx_buffer, udp_tx_buffer);
-
-                            socket
-                                .bind((IpAddress::from(wg.source_peer_ip), client_port.0))
-                                .unwrap_or_else(|e| {
-                                    error!(
-                                        "[{}] UDP virtual client socket failed to bind: {:?}",
-                                        client_port, e
-                                    );
-                                });
-
-                                virtual_interface.add_socket(socket)
-                        });
-
-                        let client_socket = virtual_interface.get_socket::<UdpSocket>(*client_socket_handle);
                                     client_socket
                                         .send_slice(
                                             &data,
-                                (IpAddress::from(destination.ip()), destination.port()).into(),
+                                            UdpMetadata::from(port_forward.destination),
                                         )
                                         .unwrap_or_else(|e| {
                                             error!(
                                                 "[{}] Failed to send data to virtual server: {:?}",
-                                    client_port, e
+                                                virtual_port, e
                                             );
                                         });
                                 }
                             }
                         }
+                        if client_socket.can_recv() {
+                            match client_socket.recv() {
+                                Ok((data, _peer)) => {
+                                    if !data.is_empty() {
+                                        endpoint.send(Event::RemoteData(*virtual_port, data.to_vec().into()));
+                                    }
+                                }
+                                Err(e) => {
+                                    error!(
+                                        "Failed to read from virtual client socket: {:?}", e
+                                    );
+                                }
+                            }
+                        }
+                    }
+
+                    // The virtual interface determines the next time to poll (this is to reduce unnecessary polls)
+                    next_poll = match iface.poll_delay(loop_start, &self.sockets) {
+                        Some(smoltcp::time::Duration::ZERO) => None,
+                        Some(delay) => {
+                            trace!("UDP Virtual interface delayed next poll by {}", delay);
+                            Some(tokio::time::Instant::now() + Duration::from_millis(delay.total_millis()))
+                        },
+                        None => None,
+                    };
+                }
+                event = endpoint.recv() => {
+                    match event {
+                        Event::LocalData(port_forward, virtual_port, data) => {
+                            if let Some(send_queue) = send_queue.get_mut(&virtual_port) {
+                                // Client socket already exists
+                                send_queue.push_back((port_forward, data));
+                            } else {
+                                // Client socket does not exist
+                                let client_socket = UdpVirtualInterface::new_client_socket(self.source_peer_ip, virtual_port)?;
+                                let client_handle = self.sockets.add(client_socket);
+
+                                // Add handle to map
+                                port_client_handle_map.insert(virtual_port, client_handle);
+                                send_queue.insert(virtual_port, VecDeque::from(vec![(port_forward, data)]));
+                            }
+                            next_poll = None;
+                        }
+                        Event::VirtualDeviceFed(PortProtocol::Udp) => {
+                            next_poll = None;
+                        }
+                        _ => {}
+                    }
+                }
+            }
         }
     }
 }
+
+const fn addr_length(addr: &IpAddress) -> u8 {
+    match addr.version() {
+        IpVersion::Ipv4 => 32,
+        IpVersion::Ipv6 => 128,
+    }
+}

src/wg.rs

@@ -1,15 +1,18 @@
-use std::net::{IpAddr, Ipv4Addr, Ipv6Addr, SocketAddr};
+use std::net::{IpAddr, SocketAddr};
 use std::time::Duration;
 
+use crate::Bus;
 use anyhow::Context;
+use async_recursion::async_recursion;
+use boringtun::noise::errors::WireGuardError;
 use boringtun::noise::{Tunn, TunnResult};
 use log::Level;
-use smoltcp::wire::{IpProtocol, IpVersion, Ipv4Packet, Ipv6Packet, TcpPacket, UdpPacket};
+use smoltcp::wire::{IpProtocol, IpVersion, Ipv4Packet, Ipv6Packet};
 use tokio::net::UdpSocket;
-use tokio::sync::RwLock;
+use tokio::sync::Mutex;
 
 use crate::config::{Config, PortProtocol};
-use crate::virtual_iface::VirtualPort;
+use crate::events::Event;
 
 /// The capacity of the channel for received IP packets.
 pub const DISPATCH_CAPACITY: usize = 1_000;
@@ -21,35 +24,31 @@ const MAX_PACKET: usize = 65536;
 pub struct WireGuardTunnel {
     pub(crate) source_peer_ip: IpAddr,
     /// `boringtun` peer/tunnel implementation, used for crypto & WG protocol.
-    peer: Box<Tunn>,
+    peer: Mutex<Box<Tunn>>,
     /// The UDP socket for the public WireGuard endpoint to connect to.
     udp: UdpSocket,
     /// The address of the public WireGuard endpoint (UDP).
     pub(crate) endpoint: SocketAddr,
-    /// Maps virtual ports to the corresponding IP packet dispatcher.
+    /// Event bus
-    virtual_port_ip_tx: dashmap::DashMap<VirtualPort, tokio::sync::mpsc::Sender<Vec<u8>>>,
+    bus: Bus,
-    /// IP packet dispatcher for unroutable packets. `None` if not initialized.
-    sink_ip_tx: RwLock<Option<tokio::sync::mpsc::Sender<Vec<u8>>>>,
 }
 
 impl WireGuardTunnel {
     /// Initialize a new WireGuard tunnel.
-    pub async fn new(config: &Config) -> anyhow::Result<Self> {
+    pub async fn new(config: &Config, bus: Bus) -> anyhow::Result<Self> {
         let source_peer_ip = config.source_peer_ip;
-        let peer = Self::create_tunnel(config)?;
+        let peer = Mutex::new(Box::new(Self::create_tunnel(config)?));
-        let udp = UdpSocket::bind("0.0.0.0:0")
-            .await
-            .with_context(|| "Failed to create UDP socket for WireGuard connection")?;
         let endpoint = config.endpoint_addr;
-        let virtual_port_ip_tx = Default::default();
+        let udp = UdpSocket::bind(config.endpoint_bind_addr)
+            .await
+            .context("Failed to create UDP socket for WireGuard connection")?;
 
         Ok(Self {
             source_peer_ip,
             peer,
             udp,
             endpoint,
-            virtual_port_ip_tx,
+            bus,
-            sink_ip_tx: RwLock::new(None),
         })
     }
 
@@ -57,12 +56,16 @@ impl WireGuardTunnel {
     pub async fn send_ip_packet(&self, packet: &[u8]) -> anyhow::Result<()> {
         trace_ip_packet("Sending IP packet", packet);
         let mut send_buf = [0u8; MAX_PACKET];
-        match self.peer.encapsulate(packet, &mut send_buf) {
+        let encapsulate_result = {
+            let mut peer = self.peer.lock().await;
+            peer.encapsulate(packet, &mut send_buf)
+        };
+        match encapsulate_result {
             TunnResult::WriteToNetwork(packet) => {
                 self.udp
                     .send_to(packet, self.endpoint)
                     .await
-                    .with_context(|| "Failed to send encrypted IP packet to WireGuard endpoint.")?;
+                    .context("Failed to send encrypted IP packet to WireGuard endpoint.")?;
                 debug!(
                     "Sent {} bytes to WireGuard endpoint (encrypted IP packet)",
                     packet.len()
@@ -84,31 +87,20 @@ impl WireGuardTunnel {
         Ok(())
     }
 
-    /// Register a virtual interface (using its assigned virtual port) with the given IP packet `Sender`.
+    pub async fn produce_task(&self) -> ! {
-    pub fn register_virtual_interface(
+        trace!("Starting WireGuard production task");
-        &self,
+        let mut endpoint = self.bus.new_endpoint();
-        virtual_port: VirtualPort,
+
-        sender: tokio::sync::mpsc::Sender<Vec<u8>>,
+        loop {
-    ) -> anyhow::Result<()> {
+            if let Event::OutboundInternetPacket(data) = endpoint.recv().await {
-        self.virtual_port_ip_tx.insert(virtual_port, sender);
+                match self.send_ip_packet(&data).await {
-        Ok(())
+                    Ok(_) => {}
+                    Err(e) => {
+                        error!("{:?}", e);
+                    }
+                }
             }
-
-    /// Register a virtual interface (using its assigned virtual port) with the given IP packet `Sender`.
-    pub async fn register_sink_interface(
-        &self,
-    ) -> anyhow::Result<tokio::sync::mpsc::Receiver<Vec<u8>>> {
-        let (sender, receiver) = tokio::sync::mpsc::channel(DISPATCH_CAPACITY);
-
-        let mut sink_ip_tx = self.sink_ip_tx.write().await;
-        *sink_ip_tx = Some(sender);
-
-        Ok(receiver)
         }
-
-    /// Releases the virtual interface from IP dispatch.
-    pub fn release_virtual_interface(&self, virtual_port: VirtualPort) {
-        self.virtual_port_ip_tx.remove(&virtual_port);
     }
 
     /// WireGuard Routine task. Handles Handshake, keep-alive, etc.
@@ -117,7 +109,14 @@ impl WireGuardTunnel {
 
         loop {
             let mut send_buf = [0u8; MAX_PACKET];
-            match self.peer.update_timers(&mut send_buf) {
+            let tun_result = { self.peer.lock().await.update_timers(&mut send_buf) };
+            self.handle_routine_tun_result(tun_result).await;
+        }
+    }
+
+    #[async_recursion]
+    async fn handle_routine_tun_result<'a: 'async_recursion>(&self, result: TunnResult<'a>) -> () {
+        match result {
             TunnResult::WriteToNetwork(packet) => {
                 debug!(
                     "Sending routine packet of {} bytes to WireGuard endpoint",
@@ -133,6 +132,18 @@ impl WireGuardTunnel {
                     }
                 };
             }
+            TunnResult::Err(WireGuardError::ConnectionExpired) => {
+                warn!("Wireguard handshake has expired!");
+
+                let mut buf = vec![0u8; MAX_PACKET];
+                let result = self
+                    .peer
+                    .lock()
+                    .await
+                    .format_handshake_initiation(&mut buf[..], false);
+
+                self.handle_routine_tun_result(result).await
+            }
             TunnResult::Err(e) => {
                 error!(
                     "Failed to prepare routine packet for WireGuard endpoint: {:?}",
@@ -146,14 +157,14 @@ impl WireGuardTunnel {
             other => {
                 warn!("Unexpected WireGuard routine task state: {:?}", other);
             }
-            }
+        };
-        }
     }
 
     /// WireGuard consumption task. Receives encrypted packets from the WireGuard endpoint,
     /// decapsulates them, and dispatches newly received IP packets.
     pub async fn consume_task(&self) -> ! {
         trace!("Starting WireGuard consumption task");
+        let endpoint = self.bus.new_endpoint();
 
         loop {
             let mut recv_buf = [0u8; MAX_PACKET];
@@ -170,7 +181,11 @@ impl WireGuardTunnel {
             };
 
             let data = &recv_buf[..size];
-            match self.peer.decapsulate(None, data, &mut send_buf) {
+            let decapsulate_result = {
+                let mut peer = self.peer.lock().await;
+                peer.decapsulate(None, data, &mut send_buf)
+            };
+            match decapsulate_result {
                 TunnResult::WriteToNetwork(packet) => {
                     match self.udp.send_to(packet, self.endpoint).await {
                         Ok(_) => {}
@@ -179,9 +194,10 @@ impl WireGuardTunnel {
                             continue;
                         }
                     };
+                    let mut peer = self.peer.lock().await;
                     loop {
                         let mut send_buf = [0u8; MAX_PACKET];
-                        match self.peer.decapsulate(None, &[], &mut send_buf) {
+                        match peer.decapsulate(None, &[], &mut send_buf) {
                             TunnResult::WriteToNetwork(packet) => {
                                 match self.udp.send_to(packet, self.endpoint).await {
                                     Ok(_) => {}
@@ -206,38 +222,8 @@ impl WireGuardTunnel {
                     // For debugging purposes: parse packet
                     trace_ip_packet("Received IP packet", packet);
 
-                    match self.route_ip_packet(packet) {
+                    if let Some(proto) = self.route_protocol(packet) {
-                        RouteResult::Dispatch(port) => {
+                        endpoint.send(Event::InboundInternetPacket(proto, packet.to_vec().into()));
-                            let sender = self.virtual_port_ip_tx.get(&port);
-                            if let Some(sender_guard) = sender {
-                                let sender = sender_guard.value();
-                                match sender.send(packet.to_vec()).await {
-                                    Ok(_) => {
-                                        trace!(
-                                            "Dispatched received IP packet to virtual port {}",
-                                            port
-                                        );
-                                    }
-                                    Err(e) => {
-                                        error!(
-                                            "Failed to dispatch received IP packet to virtual port {}: {}",
-                                            port, e
-                                        );
-                                    }
-                                }
-                            } else {
-                                warn!("[{}] Race condition: failed to get virtual port sender after it was dispatched", port);
-                            }
-                        }
-                        RouteResult::Sink => {
-                            trace!("Sending unroutable IP packet received from WireGuard endpoint to sink interface");
-                            self.route_ip_sink(packet).await.unwrap_or_else(|e| {
-                                error!("Failed to send unroutable IP packet to sink: {:?}", e)
-                            });
-                        }
-                        RouteResult::Drop => {
-                            trace!("Dropped unroutable IP packet received from WireGuard endpoint");
-                        }
                     }
                 }
                 _ => {}
@@ -245,102 +231,46 @@ impl WireGuardTunnel {
         }
     }
 
-    fn create_tunnel(config: &Config) -> anyhow::Result<Box<Tunn>> {
+    fn create_tunnel(config: &Config) -> anyhow::Result<Tunn> {
+        let private = config.private_key.as_ref().clone();
+        let public = *config.endpoint_public_key.as_ref();
+
         Tunn::new(
-            config.private_key.clone(),
+            private,
-            config.endpoint_public_key.clone(),
+            public,
-            None,
+            config.preshared_key,
             config.keepalive_seconds,
             0,
             None,
         )
         .map_err(|s| anyhow::anyhow!("{}", s))
-        .with_context(|| "Failed to initialize boringtun Tunn")
+        .context("Failed to initialize boringtun Tunn")
     }
 
-    /// Makes a decision on the handling of an incoming IP packet.
+    /// Determine the inner protocol of the incoming IP packet (TCP/UDP).
-    fn route_ip_packet(&self, packet: &[u8]) -> RouteResult {
+    fn route_protocol(&self, packet: &[u8]) -> Option<PortProtocol> {
         match IpVersion::of_packet(packet) {
             Ok(IpVersion::Ipv4) => Ipv4Packet::new_checked(&packet)
                 .ok()
                 // Only care if the packet is destined for this tunnel
-                .filter(|packet| Ipv4Addr::from(packet.dst_addr()) == self.source_peer_ip)
+                .filter(|packet| packet.dst_addr() == self.source_peer_ip)
-                .map(|packet| match packet.protocol() {
+                .and_then(|packet| match packet.next_header() {
-                    IpProtocol::Tcp => Some(self.route_tcp_segment(packet.payload())),
+                    IpProtocol::Tcp => Some(PortProtocol::Tcp),
-                    IpProtocol::Udp => Some(self.route_udp_datagram(packet.payload())),
+                    IpProtocol::Udp => Some(PortProtocol::Udp),
                     // Unrecognized protocol, so we cannot determine where to route
-                    _ => Some(RouteResult::Drop),
+                    _ => None,
-                })
+                }),
-                .flatten()
-                .unwrap_or(RouteResult::Drop),
             Ok(IpVersion::Ipv6) => Ipv6Packet::new_checked(&packet)
                 .ok()
                 // Only care if the packet is destined for this tunnel
-                .filter(|packet| Ipv6Addr::from(packet.dst_addr()) == self.source_peer_ip)
+                .filter(|packet| packet.dst_addr() == self.source_peer_ip)
-                .map(|packet| match packet.next_header() {
+                .and_then(|packet| match packet.next_header() {
-                    IpProtocol::Tcp => Some(self.route_tcp_segment(packet.payload())),
+                    IpProtocol::Tcp => Some(PortProtocol::Tcp),
-                    IpProtocol::Udp => Some(self.route_udp_datagram(packet.payload())),
+                    IpProtocol::Udp => Some(PortProtocol::Udp),
                     // Unrecognized protocol, so we cannot determine where to route
-                    _ => Some(RouteResult::Drop),
+                    _ => None,
-                })
+                }),
-                .flatten()
+            _ => None,
-                .unwrap_or(RouteResult::Drop),
-            _ => RouteResult::Drop,
-        }
-    }
-
-    /// Makes a decision on the handling of an incoming TCP segment.
-    fn route_tcp_segment(&self, segment: &[u8]) -> RouteResult {
-        TcpPacket::new_checked(segment)
-            .ok()
-            .map(|tcp| {
-                if self
-                    .virtual_port_ip_tx
-                    .get(&VirtualPort(tcp.dst_port(), PortProtocol::Tcp))
-                    .is_some()
-                {
-                    RouteResult::Dispatch(VirtualPort(tcp.dst_port(), PortProtocol::Tcp))
-                } else if tcp.rst() {
-                    RouteResult::Drop
-                } else {
-                    RouteResult::Sink
-                }
-            })
-            .unwrap_or(RouteResult::Drop)
-    }
-
-    /// Makes a decision on the handling of an incoming UDP datagram.
-    fn route_udp_datagram(&self, datagram: &[u8]) -> RouteResult {
-        UdpPacket::new_checked(datagram)
-            .ok()
-            .map(|udp| {
-                if self
-                    .virtual_port_ip_tx
-                    .get(&VirtualPort(udp.dst_port(), PortProtocol::Udp))
-                    .is_some()
-                {
-                    RouteResult::Dispatch(VirtualPort(udp.dst_port(), PortProtocol::Udp))
-                } else {
-                    RouteResult::Drop
-                }
-            })
-            .unwrap_or(RouteResult::Drop)
-    }
-
-    /// Route a packet to the IP sink interface.
-    async fn route_ip_sink(&self, packet: &[u8]) -> anyhow::Result<()> {
-        let ip_sink_tx = self.sink_ip_tx.read().await;
-
-        if let Some(ip_sink_tx) = &*ip_sink_tx {
-            ip_sink_tx
-                .send(packet.to_vec())
-                .await
-                .with_context(|| "Failed to dispatch IP packet to sink interface")
-        } else {
-            warn!(
-                "Could not dispatch unroutable IP packet to sink because interface is not active."
-            );
-            Ok(())
         }
     }
 }
@@ -364,12 +294,3 @@ fn trace_ip_packet(message: &str, packet: &[u8]) {
         }
     }
 }
-
-enum RouteResult {
-    /// Dispatch the packet to the virtual port.
-    Dispatch(VirtualPort),
-    /// The packet is not routable, and should be sent to the sink interface.
-    Sink,
-    /// The packet is not routable, and can be safely ignored.
-    Drop,
-}